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What's it like to be an alien? · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: When you look up at the night sky, you are
0:10
Speaker 1: casting your eyes on billions of star systems. It's a
0:14
Speaker 1: beautiful view, and it always makes me wonder about something.
0:17
Speaker 1: If the universe is filled with life, big, if, and
0:21
Speaker 1: if some of it is intelligent and curious, then are
0:25
Speaker 1: they looking back at us right now? Are we some
0:28
Speaker 1: bright dot in an alien sky. It's like that moment
0:32
Speaker 1: in the movies where someone is looking at a distant
0:35
Speaker 1: building through a telescope only to spot someone else looking
0:39
Speaker 1: back at them. If only other planets were close enough
0:41
Speaker 1: for us to spot alien astronomers gazing back at us
0:45
Speaker 1: like a cosmic meat cute. But even if we can't
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Speaker 1: see them, they might be out there as ignorant about
0:52
Speaker 1: us as we are, of them, staring up into those
0:55
Speaker 1: alien nights and wondering if we are out there. Or
0:58
Speaker 1: maybe they're listening to an alien physicist on an alien podcast,
1:02
Speaker 1: or maybe they don't look or listen at all, and
1:06
Speaker 1: they experienced the universe in very different ways. Hi, I'm Daniel.
1:25
Speaker 1: I'm a particle a physicist and a professor at you
1:28
Speaker 1: See Irvine, and I hope that there are alien particle
1:32
Speaker 1: physicists out there wondering what we have discovered and eager
1:36
Speaker 1: to share some notes and welcome to the podcast. Daniel
1:39
Speaker 1: and Jorge Explain the Universe, a production of I Heart
1:42
Speaker 1: Media in which we explore all the questions being asked
1:45
Speaker 1: by humans. Whether you're a particle physicist, a dentist, or
1:49
Speaker 1: a long haul driver, we all wonder about how the
1:52
Speaker 1: universe works, and we all long to understand it. And
1:55
Speaker 1: on this podcast we ask those questions and do our
1:58
Speaker 1: best to answer them. But we don't pretend to know
2:01
Speaker 1: everything or to have all of the answers. One of
2:04
Speaker 1: our goals is to bring you up to speed, to
2:06
Speaker 1: the very forefront of human knowledge, so that you can
2:09
Speaker 1: share a spot with the rest of us looking into
2:12
Speaker 1: the abyss of everything that humanity does not yet understand,
2:16
Speaker 1: because we want to know how the universe works. We
2:19
Speaker 1: are a curious species, always wondering, and one of the
2:22
Speaker 1: things that we wonder is why do we wonder so much?
2:26
Speaker 1: Is it a natural product of being intelligent problem solving
2:29
Speaker 1: creatures or is it just us? We see other animals
2:33
Speaker 1: on Earth being curious. Dogs, cats, monkeys, dolphins all outwardly
2:37
Speaker 1: act as if they are intrigued by new things, by puzzles,
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Speaker 1: they have not yet solved, which is why philosophers have
2:44
Speaker 1: long wondered what's it like to see the world through
2:47
Speaker 1: the eyes of a cat, or with the nose of
2:49
Speaker 1: a dog, or the echolocation of a dolphin. One of
2:52
Speaker 1: the most famous papers in philosophy is called what is
2:55
Speaker 1: it like to be a bat? The short version is
2:58
Speaker 1: we'll never know because a bat likely experiences the world
3:02
Speaker 1: very differently than we do. But bats don't have our intelligence.
3:06
Speaker 1: So cast your mind back out into space and wonder
3:10
Speaker 1: about that intelligent alien creature or blob or tree or
3:14
Speaker 1: floating ball of plasma that might be looking back at us.
3:18
Speaker 1: Can we imagine what their experience is like? So on
3:22
Speaker 1: today's episode, we'll ask the question, what's it like to
3:30
Speaker 1: be an alien? Obviously it's not a question we can
3:34
Speaker 1: answer today, but that doesn't mean that we can't make
3:37
Speaker 1: some progress. We can turn our minds back to the
3:40
Speaker 1: Earth and study the diversity of life here. It's random outcomes,
3:44
Speaker 1: it's consistent convergence is it's diversity and homogeneity, and maybe
3:49
Speaker 1: gain some insight into how aliens perceive and experience the universe.
3:53
Speaker 1: My co host and friend Jorge is on vacation this week,
3:56
Speaker 1: So I've invited a guest to come and join me
3:58
Speaker 1: in today's conversation about the alien experience. Dr Arik Kirshenbaum
4:16
Speaker 1: is a zoologist at the University of Cambridge. He studies
4:19
Speaker 1: the evolution of acoustic communications in different animals, particularly the
4:23
Speaker 1: role that communication plays in the evolution of cooperation. He
4:26
Speaker 1: works with a number of different species, including wolves, dolphins,
4:29
Speaker 1: and higher axes, and he's the author of the book
4:32
Speaker 1: The Zoologist Guide to the Galaxy. What Animals on Earth
4:35
Speaker 1: Reveal about Aliens. Now, we can't study aliens in the flesh,
4:39
Speaker 1: but if the principles that guided the development of biological
4:42
Speaker 1: life on Earth natural selection also apply elsewhere, then we
4:45
Speaker 1: can expect it may produce similar results. Not everything on Earth,
4:49
Speaker 1: of course, is inevitable. Some of the nature is random chance,
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Speaker 1: media strikes and other pivot points. But some things crop
4:55
Speaker 1: up often enough that they may be inevitable even on
4:58
Speaker 1: other planets. I read this book and learned lot, and
5:00
Speaker 1: so I was excited to chat with Dr Kristen Boum.
5:02
Speaker 1: So it's my pleasure to welcome Eric to the podcast.
5:05
Speaker 1: Thank you very much for joining us, Thank you for
5:07
Speaker 1: inviting me. So I love that on your website you
5:10
Speaker 1: list the organisms that you study, and there's wolves, dolphins,
5:14
Speaker 1: higher axes, and aliens. Is it typical for zoologists to
5:18
Speaker 1: think about aliens? Is astro zoology and burgeoning field or
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Speaker 1: are you the pioneer? It's not typical. It's not a
5:24
Speaker 1: burgeoning field. And you know, the field of astrobiology is big.
5:28
Speaker 1: The field of astrobiology is big and really burgeoning because
5:32
Speaker 1: you know, some of the some of the new developments
5:34
Speaker 1: that we've had, both in terms of instruments like James
5:37
Speaker 1: Webb and discoveries that can be made about the atmospheres
5:40
Speaker 1: of other planets and things like that has really pushed
5:43
Speaker 1: forward interest in the origin of life and and and
5:47
Speaker 1: the possible chemical nature of life on other planets. But
5:50
Speaker 1: also it's not just the instrumentation. You know, there's been
5:52
Speaker 1: a lot of breakthroughs really in new theoretical ideas about
5:56
Speaker 1: how life could arise. And so there are a lot
5:58
Speaker 1: of astrobologists around. There aren't really very many as rozoologists.
6:03
Speaker 1: And you know that's because, like you said that we
6:06
Speaker 1: can't actually observe any any alien animals, so so one
6:10
Speaker 1: might think as the much point. Really it's a bit
6:12
Speaker 1: of a waste of a career, but no as a
6:14
Speaker 1: as an evolutionary biologist, which is what I really am.
6:17
Speaker 1: The conclusions that I draw about evolutionary biology, they're generally applicable,
6:21
Speaker 1: you know, they apply on on other planets. I think
6:24
Speaker 1: people are going to start to come around to this idea.
6:28
Speaker 1: The understanding the ecology and the ecosystem and the evolution
6:32
Speaker 1: of life on other planets is something we have to
6:35
Speaker 1: start thinking about now that we're expecting to discover planets
6:39
Speaker 1: with some form of life on them. This is something
6:42
Speaker 1: we can't ignore forever. And I really appreciate that your
6:44
Speaker 1: book makes an argument. You know, a lot of biology
6:47
Speaker 1: books I read are fun and they're studied with cool
6:49
Speaker 1: examples that are interesting to learn about, but they don't
6:52
Speaker 1: always manage to tie them together into a coherent story.
6:56
Speaker 1: So briefly, is that the argument for your book that
6:59
Speaker 1: the process of evolution that occurs on Earth is likely
7:02
Speaker 1: to also guide the evolution of animals and critters on
7:05
Speaker 1: other planets so that we can make educated guesses about
7:08
Speaker 1: what they likely look like. Yes, it's and it's even
7:11
Speaker 1: a little bit deeper than that, because natural selection is
7:14
Speaker 1: just a process. Right we've known about natural selection for
7:16
Speaker 1: a hundred and fifty years, and it's just one of
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Speaker 1: those things that's inevitable. It's going to happen everywhere. It's
7:23
Speaker 1: a very simple process. But what's happened in the last
7:26
Speaker 1: hundred and fifty years is that biologists have not just
7:29
Speaker 1: understood how evolution works, but they've understood that there are
7:33
Speaker 1: a huge range of other phenomena that arise once you
7:37
Speaker 1: start having natural selection in a collection of life forms,
7:41
Speaker 1: and the interactions between those life forms are really important.
7:45
Speaker 1: The way those life forms interact with each other, that's
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Speaker 1: what's driving the diversity on this planet. That's why we've
7:50
Speaker 1: got so many different plants, and so many different animals,
7:53
Speaker 1: and so many different beetles. It's because of the way
7:55
Speaker 1: they interact with each other, and so understanding how those
7:59
Speaker 1: interactions are driving diversity give us some much more a
8:04
Speaker 1: much deeper understanding of those processes. And if those processes,
8:08
Speaker 1: those deeper processes are also taking place on other planets,
8:11
Speaker 1: then we can start drawing some really quite deep conclusions.
8:14
Speaker 1: Just give you one example, the simplest example in my
8:16
Speaker 1: book I think is predation. Right, all life needs energy.
8:21
Speaker 1: We know all life needs energy. That's just a physical constraint.
8:24
Speaker 1: Where you're going to get your energy. Might get it
8:26
Speaker 1: from the sun, you might get it from other places.
8:28
Speaker 1: But there's lots of energy around in the other life
8:33
Speaker 1: on your planet, and sooner or later someone is going
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Speaker 1: to start taking advantage of other life forms and and
8:39
Speaker 1: and start eating them. And in that sense, by thinking
8:42
Speaker 1: about that, the way that the organisms interact with each other,
8:46
Speaker 1: we can predict things like, well, there are going to
8:48
Speaker 1: be predators, and there are going to be prey on
8:50
Speaker 1: alien planets. I really enjoyed this line in your book.
8:52
Speaker 1: I was going to call it out later. You write,
8:54
Speaker 1: predation is universal because no ecosystem can exist for long
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Speaker 1: without someone trying to take a bite out of somebody else.
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Speaker 1: The selected pressure on acquiring as much energy as possible
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Speaker 1: is just too strong. That strikes me as maybe the
9:06
Speaker 1: experience of somebody who grew up in a household with
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Speaker 1: brothers and sisters, you know, competing for enough food at
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Speaker 1: the dinner table. But it's interesting because it's not an
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Speaker 1: argument that I've heard anywhere else. Is essentially seems to
9:16
Speaker 1: be arguing that complexity arises also from interaction and competition
9:21
Speaker 1: that you're like unlikely to find an alien planet with
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Speaker 1: a really sophisticated intelligent creature and nothing else, right, an
9:28
Speaker 1: ecosystem with just like a single organism, is it is
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Speaker 1: that the argument that you're making, I think that's that's
9:33
Speaker 1: very true, and now that works on a couple of
9:35
Speaker 1: different levels. The thing about natural selection, of course, is
9:38
Speaker 1: that it has no foresight. So organisms don't evolve to
9:41
Speaker 1: be the best they can. They evolve according to the
9:44
Speaker 1: conditions in which they find them. If the conditions are simple,
9:47
Speaker 1: if the challenges they're facing a simple then they will
9:50
Speaker 1: evolve simple traits. Um if the challenges facing them are
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Speaker 1: very complex, there may be an advantage to have more
9:57
Speaker 1: complex behavioral, more complex structure. So the complexity of individuals
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Speaker 1: in an ecosystem really arises directly out of the complexity
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Speaker 1: of the challenges they face, and those challenges are almost
10:10
Speaker 1: always to do with interactions with other organisms and other
10:13
Speaker 1: few other things as well physical environment. But basically what
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Speaker 1: drives the complexity of life is the complexity of the
10:20
Speaker 1: of the interactions. So yeah, you're not going to get
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Speaker 1: intelligent technological aliens evolving in deep space, for instance, which
10:29
Speaker 1: is a bit of a trope in science fiction. You know,
10:31
Speaker 1: You've got these aliens floating through space and they're super intelligent,
10:33
Speaker 1: but that's not going to happen because their ancestors never
10:37
Speaker 1: had any challenges to overcome and they know and any
10:39
Speaker 1: interactions they had to deal with, and so that that
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Speaker 1: that kind of intelligence isn't isn't going to evolve. So yeah, yeah,
10:45
Speaker 1: I'm going with the interactions as being the key thing,
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Speaker 1: and those interactions have to be with basically objects of
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Speaker 1: another species. You can't just have interactions within a species.
10:53
Speaker 1: We're competing with your brothers and sisters for enough milk
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Speaker 1: from your mother, for example. Well you can, but the
11:00
Speaker 1: implications of that are that some organisms will develop some
11:05
Speaker 1: techniques to deal with with that situation, and other organisms
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Speaker 1: will develop different techniques to deal with with those challenges,
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Speaker 1: and then you get a divergence and then you get speciation.
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Speaker 1: And so it's almost inevitable that as the challenge has
11:17
Speaker 1: become more complex, you're going to get different different organisms.
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Speaker 1: A system with all the same organism with complex challenges
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Speaker 1: is very unlikely to persist for a long period of time.
11:27
Speaker 1: So you mentioned science fiction, Is that your experience when
11:30
Speaker 1: you read science fiction that agreetes on you because it
11:33
Speaker 1: doesn't reflect sort of the best thinking about how evolution
11:36
Speaker 1: might play out on other planets. Are you generally unimpressed,
11:39
Speaker 1: or if you read a few things that you think
11:40
Speaker 1: are actually insightful and contribute to the space of ideas,
11:44
Speaker 1: I don't I don't mind. I like science fiction, and
11:47
Speaker 1: I see its role as being a particular role, and
11:51
Speaker 1: its role is not really to inform on scientific hypotheses.
11:54
Speaker 1: And there are cases where people have made a really
11:57
Speaker 1: big effort to try and and and explore all kinds
12:01
Speaker 1: of potential ideas and potential situations using science fiction, and
12:05
Speaker 1: that's always welcome. But you know, I mean, I love
12:08
Speaker 1: a good Star Trek, and I don't really think that
12:10
Speaker 1: it's got much to do with what aliens are like.
12:12
Speaker 1: But that's okay that you know, that's that's not the
12:15
Speaker 1: end of the world. Well, Star Trek is, of course
12:17
Speaker 1: one of the most ridiculous examples, you know, humanoids that
12:19
Speaker 1: speak with sort of strange accents and funny terms of
12:22
Speaker 1: phrase and have wigglely boardheads. Are you familiar with the
12:24
Speaker 1: work of a. Greg Egan. He is a fantastic book
12:27
Speaker 1: that's one of my favorites, called Diaspora, in which they
12:30
Speaker 1: discover a water world that has a single organism in it,
12:33
Speaker 1: an algae that weaves itself into these weighing carpets that
12:37
Speaker 1: can break and reconnect in ways that actually make them
12:39
Speaker 1: a Turing machine. So that the complexity arises from the
12:43
Speaker 1: arrangement of fairly simple organisms. And you know, it's this
12:47
Speaker 1: kind of are they intelligent? Can we actually penetrate to them,
12:50
Speaker 1: can we understand what their experiences are they experiencing anything?
12:53
Speaker 1: Because the complexity arises from the combination of many organisms
12:57
Speaker 1: rather than inside a single organism. And this is a uh,
13:00
Speaker 1: this is another trope that that's quite interesting and has
13:04
Speaker 1: been explored by a number of science fiction authors. But
13:07
Speaker 1: again from an evolutionary perspective, the question has got to
13:10
Speaker 1: be why are these algae or Turing machine? How did
13:13
Speaker 1: that actually happen? You know, how did that come about?
13:16
Speaker 1: Because presumably they started with with simple algae that didn't
13:19
Speaker 1: have this complex structure. Somehow that complex structure must have
13:22
Speaker 1: come about. Now, did it come about because the algae
13:26
Speaker 1: that are organized into a complex structure were more successful
13:30
Speaker 1: and out competed the other algae. If so, there's a
13:32
Speaker 1: good mechanism that that that could have happened. But if
13:35
Speaker 1: they're just floating there and there's nothing much going on,
13:37
Speaker 1: it's it's hard to see how that could happen. So
13:40
Speaker 1: Fred Hoyle, sure you know Fred Hoyle, the famous astronomer
13:44
Speaker 1: or a fantastic science fiction book back in the fifties,
13:46
Speaker 1: The Black Cloud. It's really one of the best science
13:49
Speaker 1: fiction books ever written, and I love it dearly. But
13:53
Speaker 1: in the in the sort of introduction the forward to
13:56
Speaker 1: it to a recent edition that was written, Richard Dawkins
13:58
Speaker 1: absolutely toll or Fred Hoyle to pieces. He's dead now,
14:03
Speaker 1: of course, but tore him to pieces over his unrealistic
14:06
Speaker 1: biological assumptions that a cloud of gas floating through interstellar
14:10
Speaker 1: space could become sensured. There's just no challenges facing it,
14:15
Speaker 1: and no process of successive and progressive and gradual increasing complexity.
14:22
Speaker 1: That's what we've got to explain. If we want to
14:23
Speaker 1: explain alien life, that's what we've got to explain. So
14:26
Speaker 1: we're all, of course very interested in alien life and
14:28
Speaker 1: how it might arise, And of course we're all stuck
14:31
Speaker 1: here on Earth with no other examples to draw from.
14:34
Speaker 1: And you often hear people complain that this is you know,
14:36
Speaker 1: a single example and equals one. We don't know if
14:39
Speaker 1: what we have seen is typical or unusual. And in
14:42
Speaker 1: your book you take a different approach to this problem.
14:45
Speaker 1: Can you explain for our listeners how we escape the
14:47
Speaker 1: sort of in equals one prison. Well, the n equals
14:51
Speaker 1: one criticism is slightly disingenuous and equals one what one planet?
14:57
Speaker 1: That seems a little unrealistic since there are so many
14:59
Speaker 1: different forms on this planet. Really, what they're saying, I
15:03
Speaker 1: think is an equals one biochemistry, because that's really what
15:06
Speaker 1: unites all life on Earth, and we only have one
15:09
Speaker 1: example of a system of a biochemical system that can
15:12
Speaker 1: produce life. Apart from the biochemistry, there's sufficient diversity here
15:17
Speaker 1: that there's no justification for saying it's only one example.
15:20
Speaker 1: Is it a problem that we only have one example
15:23
Speaker 1: of one kind of biochemistry when when talking about alien life, Well,
15:27
Speaker 1: it's not a problem for me because everything I do
15:30
Speaker 1: totally ignores the biochemistry. You know, when you think about
15:33
Speaker 1: about evolution and natural selection and evolutionary biology, it doesn't
15:38
Speaker 1: really matter on what biochemical framework organisms are based. They
15:42
Speaker 1: can be based on DNA, they could be based on
15:44
Speaker 1: some other some other structure. People like to ask whether
15:48
Speaker 1: carbon chemistry is necessary. I mean, most people think that
15:52
Speaker 1: carbon chemistry probably is necessary, but that's from theoretical considerations,
15:56
Speaker 1: not from empirical observations. So I mean, I think you
16:01
Speaker 1: can criticize descriptions of intelligent life technological life on the
16:06
Speaker 1: basis of their only being one example, and that becomes
16:09
Speaker 1: particularly problematic when we think about language. So we only
16:12
Speaker 1: have one example of language, and that really is a problem.
16:16
Speaker 1: But I think to say that we only have one
16:17
Speaker 1: example of life is not really true at all. So
16:20
Speaker 1: the argument you're making is that we have many examples
16:23
Speaker 1: of life responding to similar circumstances, and for example, coming
16:28
Speaker 1: up with similar solutions wings on bats and wings on
16:31
Speaker 1: birds and wings on insects, for example, suggests that flight
16:34
Speaker 1: might be a common outcome of animal evolution. Is that
16:38
Speaker 1: the argument that's right? And if you want to take
16:40
Speaker 1: the unequals one complaint or objections seriously and honestly, then
16:44
Speaker 1: you would have to ask yourself, does the fact that
16:47
Speaker 1: birds and bats and insects all have wings is that
16:50
Speaker 1: fact somehow the result of some commonality the equals one commonality,
16:57
Speaker 1: the fact that they are all on the planet Earth,
16:59
Speaker 1: or the fact that they are all based on carbon chemistry.
17:02
Speaker 1: Is that does that really explain this commonality of wings?
17:06
Speaker 1: And it's almost impossible to answer yesterday. It's very hard
17:08
Speaker 1: to see how the fact that wings evolved independently three
17:11
Speaker 1: times could really possibly be based on the commonality between
17:14
Speaker 1: these organisms. The only thing they have in common is
17:17
Speaker 1: that there are bilaterally symmetrical, so they have one wing
17:21
Speaker 1: or two wings on each side of their body because
17:24
Speaker 1: they have an access of symmetry down the middle. They
17:26
Speaker 1: have a left side and the right side, and that
17:28
Speaker 1: certainly is sheard. All those three organisms evolved from a
17:32
Speaker 1: common ancestor that was symmetrical. So that's potential argument. But
17:36
Speaker 1: my counter argument that is that symmetry is so incredibly
17:39
Speaker 1: useful that we're going to see it on other planets
17:41
Speaker 1: as well. So to make the argument that the kind
17:44
Speaker 1: of things we see on Earth are likely to also
17:47
Speaker 1: crop up in alien animals, what assumptions are we making exactly?
17:50
Speaker 1: Let's be explicit about them. Were assuming that evolution is
17:54
Speaker 1: a universal process that happens here, it's going to happen everywhere.
17:57
Speaker 1: Aren't you also requiring that the conditions are similar? I mean,
18:02
Speaker 1: evolution is as you say, in response to the circumstances,
18:05
Speaker 1: are we assuming then that there are rocky planets, that
18:07
Speaker 1: there's air for things to learn to fly through? For example,
18:10
Speaker 1: I think the two kinds of assumptions based on what
18:14
Speaker 1: you mean by life being similar to life on Earth,
18:17
Speaker 1: I think that there are assumptions that support the claim
18:21
Speaker 1: that evolution and natural selection and all these processes that
18:24
Speaker 1: we understand very well from life on Earth, that they
18:27
Speaker 1: will apply on other planets. There are certain assumptions there,
18:30
Speaker 1: and those are assumptions like the basic assumptions of natural selection,
18:33
Speaker 1: that organisms reproduce, that organisms vary, that they're different in
18:38
Speaker 1: their characteristics, and that they can pass that difference on
18:41
Speaker 1: to their offspring, and that those differences have an effect
18:44
Speaker 1: on on how they survive and reproduce. And those are
18:47
Speaker 1: the basic assumptions of natural selection. As long as those
18:50
Speaker 1: assumptions are met, natural selection will occur. Can I stop
18:54
Speaker 1: you there and ask you about one of those passing
18:56
Speaker 1: information onto your offspring mean that fundamentally is rooted in
19:00
Speaker 1: the biochemistry of life on Earth, right? Can you imagine
19:03
Speaker 1: a different fundamental biochemistry for a life that has a
19:06
Speaker 1: different sort of process for passing along information that might
19:10
Speaker 1: lead to widely different sort of higher level evolution. Unfortunately,
19:15
Speaker 1: if that condition isn't met, then we've lost the most
19:20
Speaker 1: important feature of natural selection, which is that complexity can accumulate.
19:24
Speaker 1: If organisms reproduce to duplicate whatever word you want to use,
19:29
Speaker 1: but don't pass on their own traits to their duplicates,
19:33
Speaker 1: then complexity cannot accumulate and you'll just be stuck in
19:37
Speaker 1: a soup of chemicals, never becoming life. So I say
19:41
Speaker 1: that these assumptions are our conditions for natural selection applying
19:46
Speaker 1: and occurring. But if they don't apply, and if it
19:49
Speaker 1: doesn't occur, then complexity cannot accumulate. So the conditions for
19:52
Speaker 1: natural selection occurring are are It's a little bit unfair
19:55
Speaker 1: of me because I am actually assuming that they are met.
19:58
Speaker 1: But then the other thing is the other direction to
20:01
Speaker 1: take it is that just because natural selection in theory
20:06
Speaker 1: occurs doesn't necessarily mean that life will achieve the kind
20:10
Speaker 1: of complexity we see on Earth. So, for instance, people
20:13
Speaker 1: have speculated that there might be life on the surface
20:16
Speaker 1: of Titan, and Titan with its lots of flowing liquid
20:19
Speaker 1: water and rivers and lakes and mountains and so on,
20:22
Speaker 1: and the fact that this liquid is not water, is irrelevant,
20:25
Speaker 1: really invented by a chemistry based on ethane or something
20:29
Speaker 1: like that. The problem is that whatever it is minus
20:33
Speaker 1: a d eighty degrees on the surface of Titan or
20:36
Speaker 1: chemical reactions will be extremely slow, and in that case,
20:40
Speaker 1: even if there is life on Titan, it really won't
20:43
Speaker 1: have had time to evolve the kind of complexity that
20:47
Speaker 1: that that we see on Earth. Life existed on us
20:49
Speaker 1: for over three and a half billion years, and for
20:52
Speaker 1: the first three billion years it was very, very very simple,
20:57
Speaker 1: So it really took a long time for complex life
20:59
Speaker 1: to get off the ground. So just because these conditions
21:02
Speaker 1: are met doesn't mean will necessarily see something like Earth.
21:06
Speaker 1: But isn't that another example of the inequals one argument.
21:08
Speaker 1: I mean, we know that life started fairly rapidly on
21:10
Speaker 1: Earth and that it didn't become complex very rapidly. Can
21:15
Speaker 1: we conclude from that that, you know, one, life is
21:17
Speaker 1: likely to start in other places because it happened rapidly
21:20
Speaker 1: on Earth and that complexity does take a long time,
21:23
Speaker 1: or were we just unlucky? So the argument that we
21:26
Speaker 1: don't know how likely it is for non alive chemicals
21:31
Speaker 1: to become alive, we don't know how how likely that
21:34
Speaker 1: spontaneous change is. Has has been a very good argument
21:38
Speaker 1: for the equals one position, and things have changed a
21:43
Speaker 1: little bit in recent years for a couple of reasons. One,
21:45
Speaker 1: of course, we've discovered so many planets. I mean, there's
21:47
Speaker 1: just so many planets. We never thought there would be
21:50
Speaker 1: billions upon billions of Earth like planets in the galaxy.
21:53
Speaker 1: So the numbers game changes a little, but it doesn't alter,
21:56
Speaker 1: of course, the fundamental objection that maybe life on Earth
22:00
Speaker 1: was a tremendous fluke and it's just not replicated anywhere else.
22:04
Speaker 1: But recently, and as I said that, the field of
22:07
Speaker 1: astrobiology has become very, very big, and a lot of
22:10
Speaker 1: people working, there's a lot of scientists working on the
22:11
Speaker 1: question of origin of life, coming up with a lot
22:14
Speaker 1: of hypotheses that seemed to indicate that there are potentially
22:20
Speaker 1: many routes to life arising from non life, different by
22:24
Speaker 1: chemical propositions, different ways of getting chemicals to combine stably
22:30
Speaker 1: and make reproducing molecules, and and and so on, and
22:34
Speaker 1: the general feeling, although of course it's not proven, is
22:37
Speaker 1: that that the probability of life arising from nonlife is
22:41
Speaker 1: probably not all that unlikely. Wonderful. Well, I have a
22:45
Speaker 1: lot more questions about how that all works, But first
22:47
Speaker 1: let's take a quick break. All right, we're back and
23:02
Speaker 1: we're talking to Dr Eric Curson bomb about what aliens
23:05
Speaker 1: might look like and how they might crawl across the
23:08
Speaker 1: surface of their alien planets. And we've been talking about
23:11
Speaker 1: the likelihood of life starting on other planets, and also
23:14
Speaker 1: the likelihood that it looks similar to ours, whether it
23:17
Speaker 1: shares with us movement or communication or intelligence or these
23:21
Speaker 1: kinds of features. And I want to get back to
23:23
Speaker 1: a question I think I interrupted your answer, and I
23:25
Speaker 1: want to hear more your thoughts on this about the
23:28
Speaker 1: likelihood that life arises in our kind of context. You're
23:32
Speaker 1: absolutely right that there are billions of planets just in
23:35
Speaker 1: our galaxy, and many of them are rocky, and many
23:38
Speaker 1: of them are likely to be in a region where
23:40
Speaker 1: there's enough solar radiation to make water liquid on the surface, etcetera, etcetera.
23:45
Speaker 1: So there are many situations like Earth where life might arise.
23:49
Speaker 1: But does that mean that's the most likely place for
23:51
Speaker 1: life to arise? What about places like underground oceans that
23:55
Speaker 1: we have even in our solar system? Do we know
23:57
Speaker 1: if alien life arises, that it's most likely to arise
24:00
Speaker 1: in our kind of circumstances. We certainly don't um and
24:05
Speaker 1: as you say, underground oceans are tremendously interesting environment where
24:11
Speaker 1: we would love to explore. We are, of course somewhat
24:15
Speaker 1: limited at the moment that with our tools that are
24:19
Speaker 1: capable of looking at the taking spectrographic measurements of the
24:23
Speaker 1: composition of of the atmospheres of alien planets, that somewhat
24:28
Speaker 1: limits us two planets with reasonable atmospheres, you know, in
24:32
Speaker 1: the future. Who knows. The first indications of the sub
24:37
Speaker 1: underground oceans on on en Seladus and Europa came from observing,
24:42
Speaker 1: you know, plumes of water escaping from from underground. That
24:45
Speaker 1: may even be possible in the future with with extra
24:47
Speaker 1: planets to imagine, but it's possible. And there's been some
24:51
Speaker 1: very very interesting and peculiar suggestions from scientists, from astrobiologists
24:57
Speaker 1: about different places that that life could exist study I've
25:00
Speaker 1: heard recently a suggestion that even gas planets like like
25:04
Speaker 1: Neptune could possibly host a band or sphere of liquid
25:08
Speaker 1: water at some level in their atmosphere, so that there
25:12
Speaker 1: are many places where conditions for life might be right,
25:17
Speaker 1: and because we're still we're still far from finding out
25:21
Speaker 1: exactly what pathways led to life arising on Earth, I
25:25
Speaker 1: think it's a little bit optimistic to be to be
25:28
Speaker 1: examining those weird environments as well and trying to figure
25:30
Speaker 1: out how life might have arisen on Neptune or or
25:33
Speaker 1: or in Zeladus. But we'll get that. But in the
25:36
Speaker 1: context of the arguments in your book, for example, it
25:39
Speaker 1: seems like the assumptions were making are that evolution happens
25:43
Speaker 1: and all the details of you they are previously, and
25:45
Speaker 1: also that we're talking about sort of a similar kind
25:48
Speaker 1: of context, right, that evolution happens in the kind of
25:50
Speaker 1: biological context that we've experienced, and and we don't need
25:53
Speaker 1: to assume that that's dominant or that it doesn't happen
25:56
Speaker 1: in other context to explore what life might be like
25:59
Speaker 1: on an alien, rocky planet with water. So two things,
26:03
Speaker 1: two things to say to that. One is that when
26:06
Speaker 1: you say that the context and I presume, I mean
26:09
Speaker 1: things like, well, the fact that organisms are close to
26:11
Speaker 1: each other, that they can interact, that they're not spread
26:13
Speaker 1: out over obscenely larger area of volume. That's actually quite
26:18
Speaker 1: an easy assumption to make because again and said before
26:22
Speaker 1: about accumulating complexity, if those organisms aren't interacting, they're not
26:26
Speaker 1: going to evolve. They're not going to evolve into into
26:28
Speaker 1: the kind of complexity that we see. Then maybe alien
26:31
Speaker 1: equivalent to bacteria spotting it here and there on the
26:35
Speaker 1: surface of some planet that can't interact with each other,
26:37
Speaker 1: but there's no reason for them to evolve into more
26:40
Speaker 1: complex life forms if they never interact with anything. So
26:44
Speaker 1: I think that it's true that there are certain assumptions
26:47
Speaker 1: about about interactions and so on that I make, But
26:51
Speaker 1: that's with the hindsight, with the retrospective assumption that there
26:55
Speaker 1: will be complex life there and not just bacterial life.
26:57
Speaker 1: But the other thing that I want to say that
26:59
Speaker 1: I always have to say because it's really important to
27:01
Speaker 1: be humble about these things. There will undoubtedly be examples
27:06
Speaker 1: where I am completely wrong. I have no doubt about that,
27:09
Speaker 1: But those examples are gonna be really rare. Right. The
27:13
Speaker 1: galaxy is full of rocky planets like Earth with water
27:16
Speaker 1: on the surface, and it's full of carbon chemicals, and
27:20
Speaker 1: life which shares a lot in common with life on Earth,
27:23
Speaker 1: will be common. Sure, they'll be there'll be weird stuff.
27:26
Speaker 1: There'll be weird stuff that it's never thought of and
27:28
Speaker 1: no one has ever thought of, but that's going to
27:30
Speaker 1: be rare. Water is exceptionally common in the universe. Common
27:33
Speaker 1: chemicals are exceptionally common in the universe, and so I
27:36
Speaker 1: think it makes a lot of sense that something rather
27:39
Speaker 1: like what we see here is not going to be uncommon. Absolutely,
27:43
Speaker 1: And the argument you're making seems to be built on
27:46
Speaker 1: these convergences, these suggestions that these kind of things happen
27:50
Speaker 1: several times on Earth, so we don't have just any
27:52
Speaker 1: equals one. These are things that seem more inevitable than rare.
27:56
Speaker 1: But there are also examples here on Earth of pivot
27:59
Speaker 1: points and wins when faith took us one way and
28:01
Speaker 1: it might have gone another. You know, we have these
28:03
Speaker 1: moments in our lives. You know, when I was deciding
28:05
Speaker 1: where to go to grad school, I basically flipped a
28:07
Speaker 1: coin between two universities, and because I went to one,
28:09
Speaker 1: I ended up meeting my wife and I have these
28:12
Speaker 1: kids in My life would be very different if I
28:13
Speaker 1: hadn't gone in those other directions, you know. So can
28:16
Speaker 1: we also look at the history of life on Earth
28:19
Speaker 1: and identify those pivot points and say, if this thing
28:22
Speaker 1: about life on Earth is unlikely to be found somewhere
28:25
Speaker 1: else because it arose from this random weirdness, can we
28:28
Speaker 1: also make those kind of observations, not just find the commonalities. Well? Possibly,
28:33
Speaker 1: But I loved your example. If the coin had gone
28:35
Speaker 1: the other way, no disrespect your wife and kids, you
28:39
Speaker 1: probably would have found another wife and had other kids, right,
28:42
Speaker 1: and it still would have happened. And in that sense,
28:44
Speaker 1: I think it's a pretty good illustration of of of
28:46
Speaker 1: the convergence. Are there pivot points on Earth that led
28:50
Speaker 1: to very particular configurations of life on Earth? It's hard
28:55
Speaker 1: to think of that. I think the major pivot points
28:57
Speaker 1: on Earth, so the major mass extinctions, which are really
29:00
Speaker 1: the ones that people talk about. If you think about
29:02
Speaker 1: the Permian mass extinction, which was huge, like n of
29:07
Speaker 1: species went extinct. When life rebounded after the Permian mass extinction,
29:13
Speaker 1: it really wasn't all that different, It really wasn't. I
29:17
Speaker 1: mean certainly that that that mass extinction was a huge
29:20
Speaker 1: push and in the way that diversity developed and evolved
29:24
Speaker 1: over over the millions of years afterwards, and there's no
29:28
Speaker 1: doubt that we wouldn't have dinosaurs, and we wouldn't have primmates,
29:30
Speaker 1: we wouldn't have humans if it hadn't have been for
29:33
Speaker 1: the Permian mass extinction. But if you look at the
29:36
Speaker 1: animals that lived afterwards and the animals that lived before,
29:41
Speaker 1: they're different, But all the niches are basically still the same,
29:45
Speaker 1: basically very very similar sort of stuff going on. So
29:49
Speaker 1: clearly there are physical characteristics of Earth that determine what
29:53
Speaker 1: kind of life we have. The density of the atmosphere,
29:55
Speaker 1: the transparency of the atmosphere as well as a huge
29:57
Speaker 1: is a hugely important one in the nature of our ocean,
30:00
Speaker 1: determine the kinds of life that flying in the air
30:04
Speaker 1: and swim in the sea. But that's really the response
30:06
Speaker 1: to physical constraints constraints on on the environment, rather than
30:11
Speaker 1: the pivot points per see. And what about the one
30:13
Speaker 1: that's mostly to our hearts, you know, intelligence, you're saying
30:16
Speaker 1: that the niches are effectively the same before and after.
30:19
Speaker 1: You know, the common story that you hear is dinosaurs
30:22
Speaker 1: were wiped out by this meteor, which might have also
30:25
Speaker 1: missed Earth if had you been pulled gravitationally by another object,
30:29
Speaker 1: And that because the dinosaurs were wiped out, there was
30:31
Speaker 1: room for maimals to flourish. Dot dot dot you get
30:33
Speaker 1: humans and technological life. Are you suggesting that even if
30:35
Speaker 1: the medior hadn't hit the earth, if the dinosaurs hadn't
30:38
Speaker 1: been wiped out, that something would have arisen that was
30:40
Speaker 1: intelligent and technological not not an easy question to answer
30:44
Speaker 1: without a time machine and interfering with the course of history.
30:48
Speaker 1: But we've got some clues, right, so we can look,
30:50
Speaker 1: for instance, at if you look at a plot of
30:54
Speaker 1: the diversity of life on a since the Permian mass extinction,
30:58
Speaker 1: you'll see a pretty linear increase. I mean, it's just
31:01
Speaker 1: going up and up and up. And it's true there
31:04
Speaker 1: was a dip when that media hit and there was
31:06
Speaker 1: a nice big mass extinction there, and then diversity just
31:10
Speaker 1: kept on climbing again. So it's almost as if it
31:13
Speaker 1: just with the simple metric of how of the diversity
31:16
Speaker 1: of species, it's almost as if it didn't make much difference.
31:20
Speaker 1: You know, it changed things a little bit, maybe, but
31:23
Speaker 1: the increase in interactions between species just kept on going up.
31:28
Speaker 1: Is it possible that it could have flatlined at that point?
31:31
Speaker 1: I suppose as possible, but it seems really unlikely. Okay,
31:34
Speaker 1: it does it does seem unlikely. It's true that we
31:38
Speaker 1: can invent all kinds of stories about exactly what happened
31:41
Speaker 1: after the dinosaurs went extincts can't be very confident about them.
31:45
Speaker 1: But you know, the usual narrative goes that these nocturnal
31:48
Speaker 1: mammals all of a sudden didn't have to be so
31:50
Speaker 1: scared about coming out during the daytime, and so they
31:52
Speaker 1: could exploit niches that weren't available to them before, and
31:55
Speaker 1: so they diversified and so on. It's very hard to
31:58
Speaker 1: imagine that this kind of radiation wouldn't have happened at
32:02
Speaker 1: some point. It just seems like the opportunities were there,
32:06
Speaker 1: and opportunities get exploited in evolutionary time, they really do.
32:12
Speaker 1: That might be the first time I ever heard somebody
32:13
Speaker 1: say the phrase nice, big mass extinction. But I suppose
32:17
Speaker 1: from an evolutionary biologists that is the way you look
32:20
Speaker 1: at it. Well, I want to dig a little bit
32:25
Speaker 1: more into thinking about the details of animals on alien planets,
32:30
Speaker 1: because you go well beyond these sort of general arguments,
32:32
Speaker 1: and you talk very specifically about what we can learn
32:34
Speaker 1: about alien animals from animals on Earth. And I want
32:38
Speaker 1: to focus first on senses. You know, here on Earth
32:42
Speaker 1: we have a wide variety of senses, but humans don't
32:45
Speaker 1: have all of them. Right, There are certainly senses that
32:47
Speaker 1: exist in the animal kingdom that don't exist in humans.
32:50
Speaker 1: What can we say about what aliens might experience? Are
32:53
Speaker 1: they're likely to be able to sense magnetism the way
32:56
Speaker 1: birds do, or sense electric fields the way fish can do.
32:59
Speaker 1: Things about senses sensors are really interesting. One is that
33:02
Speaker 1: centers um really really constrained by physics. Right, there's just
33:07
Speaker 1: some things that you can and can't do. In a vacuum,
33:09
Speaker 1: you're not going to use sound, it's not going to happen.
33:11
Speaker 1: So you know, in an opaque atmosphere, you're not going
33:15
Speaker 1: to use light. So there's a lot of stuff that's
33:17
Speaker 1: really easy to predict just based on the physics. But
33:22
Speaker 1: as a biologist, I don't want to spend too much
33:24
Speaker 1: time talking about physics. And from the evolutionary perspective, there's
33:27
Speaker 1: another really interesting thing about senses, which is that senses
33:31
Speaker 1: evolved because they gave an advantage. They gave an advantage
33:34
Speaker 1: to some organism. Now, typically that advantage would be finding food.
33:38
Speaker 1: So if you have an amba and it's in water,
33:42
Speaker 1: and it detects a concentration gradient of of of nutrients
33:47
Speaker 1: and it can move up that that concentration gradient because
33:51
Speaker 1: that ability gives it a definite advantage. It gets more
33:53
Speaker 1: food that way. And senses have to be understood in
33:58
Speaker 1: terms of what advantage they give. It's a huge you know,
34:02
Speaker 1: it's this huge idea that aliens are going to have
34:04
Speaker 1: these super senses and they're gonna have these wonderful things
34:07
Speaker 1: that we don't even imagine, and they can they have
34:10
Speaker 1: all these incredible abilities that we can't conceive. Or maybe,
34:14
Speaker 1: but only if it gave their ancestors an advantage, only
34:19
Speaker 1: if the organisms from which they evolved, and probably the
34:22
Speaker 1: organisms from which they evolved a long long time ago.
34:25
Speaker 1: You know, they had to have the advantage. If you
34:27
Speaker 1: look at all the senses that exist primarily in animals today,
34:31
Speaker 1: They've been around since the simplest animals. Sensing is a
34:34
Speaker 1: really crucial thing for animals. I should probably mention I'm
34:38
Speaker 1: sure we'll come up against this again when we talk
34:40
Speaker 1: about intelligence, but I should probably mentioned why I talk
34:42
Speaker 1: about animals all the time and what I mean by animals,
34:45
Speaker 1: because animals are something quite different. You know, animals have
34:49
Speaker 1: a big challenge, which is moving around and finding food
34:54
Speaker 1: and avoiding becoming someone else's food, and finding a mate,
34:56
Speaker 1: and all the spatial constraint where do you go and
35:00
Speaker 1: how can you go? And where can you go? Really
35:02
Speaker 1: drives a lot of complexity in the animal world because
35:04
Speaker 1: they need to solve these spatial problems. Sensing is a
35:08
Speaker 1: is a perfect exam of the reason that animals sense
35:10
Speaker 1: and plants sensors are much more simple than than animal
35:13
Speaker 1: senses because plants don't need to move. Animals need to
35:16
Speaker 1: decide do I go left or do I go right? Now?
35:19
Speaker 1: Aliens may have organisms that look like plants that you
35:24
Speaker 1: may have animals like groot right, that's a plant that
35:28
Speaker 1: moves around. I would call that an animal because for me,
35:30
Speaker 1: an animal is something that has to move and make
35:33
Speaker 1: decisions about moving in the moment you have to make
35:35
Speaker 1: decisions about moving. You need sensing. You need to be
35:38
Speaker 1: able to sense the world around you. And so why,
35:40
Speaker 1: for example, did our ancestors not need to sense electric
35:44
Speaker 1: fields or magnetic fields, but the ancestors of birds and
35:47
Speaker 1: fish did. Can you not imagine any circumstance in which
35:50
Speaker 1: that would be an advantage to us using electric fields
35:52
Speaker 1: to sense the presence of fish, for example, in water,
35:54
Speaker 1: you know, while hunting in shallow lakes. Is there no
35:57
Speaker 1: circumstance in which case those other senses would have been
35:59
Speaker 1: an advantage to our ancestors are And just as though
36:02
Speaker 1: our advantages to us having wings, right, who wouldn't want wings?
36:05
Speaker 1: And not saying it's not an advantage, But the evolutionary
36:09
Speaker 1: path that we followed is constrained by what our ancestors
36:14
Speaker 1: constrained by the cost benefit analysis of our ancestors. So
36:18
Speaker 1: you know, our ancestors were better off evolving big guys
36:23
Speaker 1: that served them much better than an electric sense. Electric
36:28
Speaker 1: sensing is really really complicated. It's very very difficult. It
36:31
Speaker 1: requires very very specific organs in your body, and if
36:34
Speaker 1: you really don't use them very much, then it's just
36:38
Speaker 1: not worth it. So our ancestors didn't benefit at all,
36:42
Speaker 1: wouldn't have benefited at all from electric sensing, and so
36:45
Speaker 1: they didn't have them. But we might like wings now,
36:47
Speaker 1: you know, you might even think that our ancestors could
36:49
Speaker 1: have benefited from wings sort of climbing through the trees
36:52
Speaker 1: in the jungle, but they were constrained by their ancestors
36:55
Speaker 1: as well, and not the simplest thing in the world
36:57
Speaker 1: to evolve. Wings to the process of evolution always involves
37:00
Speaker 1: these cost benefit trade offs, and in that cost benefit analysis,
37:05
Speaker 1: it's just it just wasn't worth a while. It just
37:07
Speaker 1: wasn't worth our ancestors, our ancestors. While So your comment
37:11
Speaker 1: about aliens and their supersenses, I take that to be
37:15
Speaker 1: an argument that probably alien animals will have some subset
37:20
Speaker 1: of the kind of senses we see here on Earth.
37:22
Speaker 1: That there isn't some new, amazing sense that they have
37:25
Speaker 1: evolved that we've never seen before. Well, that's a question
37:28
Speaker 1: for you, right, that's where the physics comes in. That's
37:30
Speaker 1: constrained by physics. It's true that animals on Earth use
37:34
Speaker 1: pretty much all of you known that the senses that
37:39
Speaker 1: we think are possible through our understanding of physics. Magnetisms
37:42
Speaker 1: are really a really rare one. It's a bit of it, right,
37:46
Speaker 1: but it's not it's not hugely important. But you know,
37:49
Speaker 1: earthlings use use pretty much everything. Is there another sense
37:52
Speaker 1: out there, like gravitational sensing or something, or neutrinos sensing? Maybe?
37:58
Speaker 1: I don't know, tell me. So that was the next
38:00
Speaker 1: question I wanted to ask you about, and I'm particularly
38:02
Speaker 1: struck by the example of magnetism. I mean, here's an
38:05
Speaker 1: example where a creature develops a sense to something that's
38:09
Speaker 1: very subtle and hard to pick up. You know, it
38:11
Speaker 1: requires a really delicate chemistry to happen in their eyeballs
38:14
Speaker 1: for them to be sensitive to these magnetic fields. And
38:17
Speaker 1: at the same time, we know from the physics at
38:20
Speaker 1: least that a lot of the universe is invisible to us. Right,
38:23
Speaker 1: we are surrounded, as you say, buy neutrinos. A hundred
38:26
Speaker 1: billion passed through every square centimeter per second, and they
38:29
Speaker 1: carry a huge amount of energy. It took a long
38:32
Speaker 1: time on Earth to develop vision and photosynthesis. Is it
38:36
Speaker 1: possible that if we waited a few billion years that
38:39
Speaker 1: plants would develop like neutrino synthesis, where microbes are learning
38:43
Speaker 1: to eat energy from neutrinos somehow? Is it impossible to
38:46
Speaker 1: imagine or do you think it's just sort of hasn't
38:48
Speaker 1: happened yet here on Earth? Impulsibles big wood, but improbable
38:54
Speaker 1: is a reasonable world. And the reason is that natural
38:57
Speaker 1: selection only works when it provides concrete advantage every step
39:03
Speaker 1: of the way. Right, You've got to have an advantage
39:06
Speaker 1: by having half a neutrino detector, And given that a
39:09
Speaker 1: neutrino detectors probably pretty complicated, you'd have to explain why
39:14
Speaker 1: having some sort of very simple, primitive ability to detect
39:18
Speaker 1: neutrinos would be an advantage, and that's very hard to do.
39:23
Speaker 1: One of the nonsense arguments against evolution is that, well,
39:28
Speaker 1: how could you evolve an eye? And half an eye
39:30
Speaker 1: is not useful? Half an eye is incredibly useful. You know,
39:34
Speaker 1: the very simplest organisms that were able to detect a
39:39
Speaker 1: shadow from a bit of light had a huge advantage,
39:43
Speaker 1: a huge advantage over over other organisms. So you would
39:45
Speaker 1: need to see something like that with one of these
39:48
Speaker 1: extra senses, one of the ones that hasn't been detected.
39:50
Speaker 1: You'd have to see a real advantage for that very
39:53
Speaker 1: simple innovation. All right, and I have lots more questions
39:56
Speaker 1: about what it's like to be an alien and experience
39:58
Speaker 1: the universe. But let's take an their quick break. Okay,
40:13
Speaker 1: we're back, and we're talking to Dr Arika Kirshenbaum about
40:17
Speaker 1: his book The Zoologist Guide to the Galaxy. And I
40:20
Speaker 1: noticed that you say the Guide to the Galaxy. Is
40:23
Speaker 1: that a tip to Douglas Adams instead of thinking about
40:26
Speaker 1: the guide to the universe. It is. But then again,
40:28
Speaker 1: even astrobiologists, and I mean like the based astrobiologists, unlike me,
40:34
Speaker 1: really our thoughts are pretty much limited to the galaxy.
40:38
Speaker 1: The galaxy is something we can know about. Unless we're
40:41
Speaker 1: talking about highly advanced technological civilizations in other galaxies, we'll
40:46
Speaker 1: never know about them. Yeah, this is I think the
40:49
Speaker 1: galaxies are really reasonable laboratory in which to work. It
40:52
Speaker 1: is true that while there are chillions of other galaxies
40:55
Speaker 1: out there, there are millions of light years away, whereas
40:58
Speaker 1: our galaxy is only tens of thousands of light years across,
41:01
Speaker 1: and so they do seem frustratingly distant. And so we
41:03
Speaker 1: were talking about sort of how aliens might sense the world,
41:06
Speaker 1: and you're making the argument that we use most of
41:09
Speaker 1: the reasonable seeming senses and everything else is probably unlikely
41:13
Speaker 1: to arise because it doesn't convey a benefit at every
41:16
Speaker 1: stage of evolution. And we talked about neutrinos, for example,
41:20
Speaker 1: and you know, for the folks and the audience who
41:21
Speaker 1: are interested in physics, we know, for example, also that
41:24
Speaker 1: the universe is filled with dark matter, and that there's
41:27
Speaker 1: kinds of radiation out there that we cannot sense directly,
41:30
Speaker 1: but we've developed these technological eyeballs in order to discover
41:33
Speaker 1: them and to see that they are part of our universe.
41:36
Speaker 1: And so I think the argument you're making is that
41:38
Speaker 1: it's unlikely for these things to naturally arise biologically in
41:42
Speaker 1: aliens unless they have a pronounced benefit along every step
41:47
Speaker 1: of the evolutionary path. And in your book you make
41:49
Speaker 1: this argument specifically about how this impacts alien civilization, and
41:53
Speaker 1: you say, for example, that alien civilization will probably rely
41:57
Speaker 1: on vocal communication rather than say, community action of complex
42:01
Speaker 1: ideas using sense. So I want to dig into that
42:03
Speaker 1: a little bit more. How building on this basic experience
42:06
Speaker 1: and sensory networks, that's likely to impact the structure of
42:09
Speaker 1: alien and civilization and alien intelligence. Yeah, and it does
42:13
Speaker 1: sound a bit too radical of a suggestion, doesn't it.
42:16
Speaker 1: The alio aliens are gonna talk like us a bit
42:19
Speaker 1: of a coincidence, But then again, you know, we are
42:22
Speaker 1: constrained by physics here. There are only so many different
42:26
Speaker 1: ways that you can convey information, and so many different channels,
42:30
Speaker 1: so many different media. There's light, this sound, there's smell,
42:34
Speaker 1: a's touch, there's vibration, there's electrical fields as magnetic fields.
42:39
Speaker 1: The list is not a lot, and I'm sure that
42:42
Speaker 1: that that entire list will be exploited by organisms here.
42:48
Speaker 1: They're everywhere across the galaxy. The question is which of
42:51
Speaker 1: those channels can be used for complex communication because technology
42:55
Speaker 1: relies on complex communication. You want to build a spaceship,
42:58
Speaker 1: want to build a radio telescope, right, you need the
43:00
Speaker 1: instructions manual. You need to be able to say this
43:03
Speaker 1: part goes plugs into into that part. So there needs
43:06
Speaker 1: to be the capacity to have a certain level of complexity.
43:10
Speaker 1: Which of those media, which of those those physical channels
43:13
Speaker 1: support that kind of complexity. Well, you know, I argue
43:18
Speaker 1: that that smell probably doesn't. There are a lot of
43:21
Speaker 1: problems with using chemical cues for communication. Loads of animals
43:26
Speaker 1: do it right. It's it's one of the oldest forms
43:28
Speaker 1: of communication, but it's always going to be simple. Smells
43:32
Speaker 1: get mixed up, they travel very slowly. It just doesn't
43:35
Speaker 1: sound like it's a reliable channel for conveying information. Vision
43:39
Speaker 1: and sound really are the two that that can hold
43:42
Speaker 1: a lot of information and are reliable over over reasonable distances.
43:46
Speaker 1: And the third one, which is really reliable and can
43:49
Speaker 1: hold even more information, is electrical fields. It seems like
43:54
Speaker 1: those three channels are the only physical channels that are
43:57
Speaker 1: capable of carrying enough information really to be a complex
44:01
Speaker 1: language and to convey complex technological ideas. We use the
44:04
Speaker 1: first two. Of course, we don't use electrical fields. There
44:07
Speaker 1: are some animals on Earth that do not many and
44:09
Speaker 1: that's really because it's actually very challenging. It's a very
44:13
Speaker 1: challenging thing to do. But I don't doubt that there
44:15
Speaker 1: could be technological alien species that have an electrical communication,
44:19
Speaker 1: electrical language. And so we're building up an argument that
44:21
Speaker 1: suggests that aliens probably move their complexity arises from competition
44:26
Speaker 1: among these bits all trying to eat each other, that
44:29
Speaker 1: they're probably communicating with each other. Does this give us
44:32
Speaker 1: enough of a sort of complexity soup to suggest that
44:35
Speaker 1: intelligence is likely to arise? How much of a reach
44:40
Speaker 1: is it to suppose that this kind of context will
44:43
Speaker 1: lead to alien intelligence. Well, for a zoologist, it's it's
44:46
Speaker 1: no leap at all. Right, A zoologist will tell you
44:49
Speaker 1: all animals are intelligent. Intelligence is a fundamental property of animals,
44:54
Speaker 1: because if we define intelligence as the ability to solve problems,
44:58
Speaker 1: that's precisely what animals have to do. They have to
45:01
Speaker 1: solve problems. They have to decide whether to turn right
45:03
Speaker 1: or to turn left. They have to find food, They
45:05
Speaker 1: have to decide whether an image that they see on
45:08
Speaker 1: their retina is a potential food source or or an
45:11
Speaker 1: animal coming towards them to eat them. Those challenges which
45:16
Speaker 1: are critically I mean, the important thing about those challenges
45:19
Speaker 1: is that these challenges are time critical. Animals have to
45:22
Speaker 1: make decisions quickly, straightaway. Is it a predator? Should I run?
45:26
Speaker 1: Should I turn left? Should I turn right? And that's intelligence.
45:30
Speaker 1: That's precisely what intelligence is. So so the simplest, simplest
45:33
Speaker 1: animal has intelligence. Now, of course you're going to say
45:38
Speaker 1: that's not fair, that's not what I meant. I meant
45:40
Speaker 1: intelligence like us, I would define human intelligence in the
45:44
Speaker 1: way that you want it to be defined. What you're
45:47
Speaker 1: really asking about is technological intelligence. Okay, there's this joke
45:52
Speaker 1: from SETI scientists that I like to tell, which is
45:55
Speaker 1: that there are two kinds of organisms in the universe,
45:58
Speaker 1: folks and critters. Folks is anyone who can build a
46:02
Speaker 1: radio telescope and criticism everything else. And the rational behind
46:06
Speaker 1: that is there might be some really intelligent alien species
46:11
Speaker 1: out there really fantastically clever. If they can't make a
46:15
Speaker 1: technology to send signals to us, we'll never know. I
46:18
Speaker 1: will never know about them unless they come and visit, right, Yeah,
46:20
Speaker 1: but they'll need that technology then, now, okay, they'll have
46:23
Speaker 1: to have that technology or will never know about them,
46:26
Speaker 1: build a radio telescope, builder, spaceship, whatever. So there is
46:29
Speaker 1: a criterion which is an interesting criterion. I wouldn't call
46:32
Speaker 1: it intelligence, because, as I said, all animals are intelligent,
46:35
Speaker 1: but there is an interesting criterion of this technological intelligence,
46:38
Speaker 1: the ability to build a radio telescope, the ability to
46:41
Speaker 1: build a spaceship come and visit us. And I think
46:43
Speaker 1: that's what you're asking, Is it something like that? I mean, essentially,
46:46
Speaker 1: I want to get to the question of whether we
46:49
Speaker 1: can make a mental connection with these aliens. How likely
46:52
Speaker 1: is it that we have enough in common that we
46:54
Speaker 1: could communicate with them and get some insight into what
46:57
Speaker 1: I think is the deepous question, which is what is
46:59
Speaker 1: it like to be an alien? How different is it
47:02
Speaker 1: from what it's like to be a human, And can
47:04
Speaker 1: from that we draw some interesting conclusions about, you know,
47:07
Speaker 1: the nature of consciousness and intelligence itself. If we find
47:10
Speaker 1: aliens to be very similar to humans. If we find
47:13
Speaker 1: them to be just alien enough that we can understand them,
47:17
Speaker 1: but they're weird enough that we can learn something about
47:19
Speaker 1: the nature of intelligence, I think would be especially interesting.
47:22
Speaker 1: So one thing I really appreciated about your book was
47:24
Speaker 1: this exploration of what we mean by intelligence, especially a
47:29
Speaker 1: part in your book where you argue that if aliens
47:31
Speaker 1: are found to be as intelligent as humans, might we
47:34
Speaker 1: consider them to actually be human. Right, you can imagine
47:37
Speaker 1: granting them rights and treating them as persons. So what
47:40
Speaker 1: do you think that we can say about alien intelligence
47:43
Speaker 1: based on what we have learned here on Earth? And
47:46
Speaker 1: is it just philosophical or is it built from a
47:48
Speaker 1: sort of argument about the experience of aliens the senses
47:52
Speaker 1: that we were talking about earlier. Well, of course, it
47:55
Speaker 1: seems very very unlikely that will ever go and there's
47:59
Speaker 1: an ali in planet and look at the different alien
48:02
Speaker 1: animals on it will be wonderful, But it seems unlikely.
48:05
Speaker 1: But if we were the Thought Experiment and we were
48:08
Speaker 1: to land on a planet, okay, most of the planets
48:10
Speaker 1: with life are just going to be bacterial slime, right,
48:13
Speaker 1: probability is a vast majority there's only been bacterial slime
48:17
Speaker 1: on Earth for two and a half billion years, and
48:20
Speaker 1: and and so chances are alien planets, most alien plants
48:23
Speaker 1: are going to be like, let's say we find one
48:24
Speaker 1: that's got complex life, and we land on that planet
48:26
Speaker 1: it's got complex life, and we look around. I claim
48:29
Speaker 1: that we will see things that appear to us the
48:32
Speaker 1: equivalent of trees, things that appear to us the equivalent
48:36
Speaker 1: of animals. Those things that appear to us the equivalent
48:38
Speaker 1: of animals will have a wide range of what we
48:42
Speaker 1: think of as intelligence. There will be slug like creatures
48:46
Speaker 1: that don't seem to have very much intelligence. There will
48:48
Speaker 1: be primate like creatures that seem to have considerably more intelligence.
48:52
Speaker 1: So I think that that diversity of intelligences is very
48:57
Speaker 1: likely to occur, and I think we would wreck ignize it.
49:00
Speaker 1: I think we would recognize the parallels with animals on
49:05
Speaker 1: our planet, because of course, intelligence will arise for exactly
49:09
Speaker 1: the same reasons as as it arose on on Earth. However,
49:13
Speaker 1: now you're asking about the technological aliens. If we can
49:17
Speaker 1: even find any of those, what are the chances that
49:20
Speaker 1: we will have basically common ground with them? It's a
49:23
Speaker 1: completely different question whether we will ever be able to
49:26
Speaker 1: learn their language, But put aside for the moment, but
49:28
Speaker 1: assuming that we could learn their language, would we be
49:32
Speaker 1: able to talk to them, would we be able to
49:34
Speaker 1: understand them? Would we be able to understand the psyche experiences?
49:37
Speaker 1: You know, if if they do use electric fields to
49:40
Speaker 1: communicate their view of the world, if you can call
49:43
Speaker 1: it a view, maybe we need to think of a
49:45
Speaker 1: new word that's kind of electric view. If they sense
49:48
Speaker 1: the world using electric fields, their perception is going to
49:51
Speaker 1: be so utterly different from ours. Would we find common
49:56
Speaker 1: ground with them? And I think you can probably guess
49:59
Speaker 1: that my aunt's there is going to be yes. And
50:02
Speaker 1: the reason that my answer is going to be yes
50:04
Speaker 1: is because if we were lucky to find such a species,
50:08
Speaker 1: the only reason they have an intelligence that is similar
50:12
Speaker 1: to ours is because they've been through a similar evolutionary
50:16
Speaker 1: history to ours. That's the only reason they would have it. Right.
50:19
Speaker 1: We don't exactly know what caused our ancestors to evolve
50:23
Speaker 1: the intelligence that put us in the place that we
50:27
Speaker 1: are now and the mess that we are now, But
50:30
Speaker 1: whatever that pathway was, it's quite likely that a similar
50:35
Speaker 1: and identical similar pathway will have evolved for these intelligent aliens.
50:39
Speaker 1: And if that's the case, then yeah, there is common ground.
50:42
Speaker 1: That seems to me a strong argument. But I also
50:46
Speaker 1: think about the kind of experiences of intelligent animals here
50:50
Speaker 1: on Earth, and I wonder about the very kind of
50:52
Speaker 1: argument you make there where you say, let's look at
50:54
Speaker 1: the variety of things we see on Earth. And you know,
50:56
Speaker 1: as we look around on Earth, we see fairly intelligent
50:58
Speaker 1: creatures that we think might have very different sort of
51:02
Speaker 1: mental internal states. You know, take for example, an octopus
51:06
Speaker 1: that has like a central brain but also seems to
51:08
Speaker 1: have semi independent arms that it passes instructions too, and
51:12
Speaker 1: then they execute them. However, they like, what is it
51:14
Speaker 1: like to be an octopus? It seems like it might
51:16
Speaker 1: be very different from the experience of being human, and
51:19
Speaker 1: that kind of barrier, that kind of different flavor of
51:21
Speaker 1: intelligence might prevent a barrier to real effective communication and
51:26
Speaker 1: you know, technological transfers. But then again, there's a barrier
51:31
Speaker 1: between us and and those animals on that we can't
51:34
Speaker 1: understand what it's like to be an octopus, right, we
51:36
Speaker 1: can't understand what it's like to be a dolphin. Why
51:39
Speaker 1: not because they don't have a language. It's because they
51:43
Speaker 1: don't have a language. I mean, if you could go
51:45
Speaker 1: up to an octopus and ask what's it like to
51:47
Speaker 1: be an octopus? You might find its answer somewhat confusing,
51:51
Speaker 1: but at least you get an answer. At least you'd
51:53
Speaker 1: have an insight into what they're thinking. And it's language
51:57
Speaker 1: that's really the key thing here. In language is the
52:00
Speaker 1: only way that we can interrogate the minds of other
52:04
Speaker 1: creatures in any detail. We can do experiments, There are
52:07
Speaker 1: experiments we can do. They are very clever experiments that
52:09
Speaker 1: we do to investigate to what extent animals understand themselves,
52:14
Speaker 1: to what extent animals understand that other animals are different individuals,
52:17
Speaker 1: and so on. But really, if you want to know
52:19
Speaker 1: how you're feeling, you know, what do you what do
52:22
Speaker 1: you think about this poem or whatever? That requires language?
52:25
Speaker 1: And now the question is are these hypothetical technological aliens
52:29
Speaker 1: of ours going to have language? Yes, technological they have language.
52:35
Speaker 1: You cannot write that spaceship Instructions book without language. You
52:39
Speaker 1: cannot build a spaceship without language. You have to say
52:42
Speaker 1: to another alien, you know, asked me the screwdriver, so
52:45
Speaker 1: that barrier that exists between us and other intelligences on
52:48
Speaker 1: Earth is a real barrier, and I agree that there
52:51
Speaker 1: are many kinds of intelligences that will be hard to understand,
52:55
Speaker 1: but at least we would have that window. May not help,
52:58
Speaker 1: may not solve the problem. We may find that that
53:01
Speaker 1: alien talking octopuses are so different from us that we
53:05
Speaker 1: simply cannot understand what they're thinking, but at least it
53:08
Speaker 1: gives us a chance. At least it gives us a window.
53:10
Speaker 1: I agree that if they're technological, it's likely that they
53:12
Speaker 1: have language, But then the question is what are the
53:14
Speaker 1: chances that they are technological? And isn't there a naive
53:18
Speaker 1: argument to make that it's unlikely that we see lots
53:20
Speaker 1: of intelligence, even fairly strong intelligence on Earth like OCTOPI
53:24
Speaker 1: that isn't technological, and only one example of the case
53:27
Speaker 1: that it is ours, and therefore it's unlikely for aliens,
53:31
Speaker 1: even intelligent aliens, to be technological on other planets. Yeah,
53:35
Speaker 1: but unfortunately, that's back to the critics argument. We would
53:37
Speaker 1: never know until we can, until we can get to
53:40
Speaker 1: those planets and count how many intelligent animals there are
53:45
Speaker 1: that haven't developed spaceships that unfortunately is a closed door
53:48
Speaker 1: to us. All talk about about talking to aliens, communicating
53:52
Speaker 1: with aliens, meeting aliens. This is all very much based
53:56
Speaker 1: on this hypothetical situation where we find highly intelligent technological
54:01
Speaker 1: aliens that that will talk to us. How likely that
54:04
Speaker 1: is we have to be a smeistic I'm afraid. So
54:07
Speaker 1: then my last question is more about you, which is
54:09
Speaker 1: why are you interested in this question, this hypothetical question
54:12
Speaker 1: of alien life? Your zoologist? Are you plenty of examples
54:15
Speaker 1: for things to steady here on Earth? Why I spend
54:17
Speaker 1: time wondering about alien life? Why not just wait until
54:20
Speaker 1: we do discover it and then you can talk about
54:22
Speaker 1: their concrete details. Why did you write this specific book
54:25
Speaker 1: as it happens? This is really it's really the subject
54:28
Speaker 1: that we just touched on. I research communication, That's what
54:31
Speaker 1: I do, and I'm interested in things like how much
54:34
Speaker 1: are our animals saying? How much are they saying to
54:35
Speaker 1: each other? How complex are the messages that they passed
54:39
Speaker 1: to each other? Big question? You know, are humans the
54:42
Speaker 1: only ones with language? And to answer those kinds of questions,
54:45
Speaker 1: raises to investigate those kinds of questions haven't exactly got
54:48
Speaker 1: answers yet to investigate those kinds of questions means we
54:52
Speaker 1: need to look at some very fundamental ideas. What is language?
54:56
Speaker 1: What is communication? Which is meaning? Right? What's the meaning?
54:59
Speaker 1: You can you have meanings without language? Does that even
55:02
Speaker 1: make any sense? Does an animal does it dolphin? Mean
55:04
Speaker 1: something when it makes particular sound? And so looking at
55:08
Speaker 1: these questions and trying to find ways to answer these
55:10
Speaker 1: questions and trying to find ways to ask animals the
55:13
Speaker 1: answer really does touch on the kinds of issues we've
55:17
Speaker 1: We've just been talking about, what is the difference between
55:20
Speaker 1: the mind of a human and the mind of a
55:23
Speaker 1: chimpanzee or the mind of a of a parrot? Why
55:26
Speaker 1: are we different? Actually? In what way are we different?
55:29
Speaker 1: Are we different? Clearly we are. We have language? How
55:32
Speaker 1: has that come about? Why has that happened? Is inevitable?
55:36
Speaker 1: As you say, maybe a language will never arise on
55:39
Speaker 1: any other planets, or maybe you will. Maybe it is inevitable.
55:43
Speaker 1: Has it arisen before on Earth? Is it only humans?
55:46
Speaker 1: These are the kinds of questions that I deal with
55:48
Speaker 1: on Earth, but you can see that they have they
55:50
Speaker 1: have implications for thinking about who are ever going to
55:52
Speaker 1: talk to? If we're ever going to meet anyone. No,
55:54
Speaker 1: I absolutely I agree. I think that framing it in
55:56
Speaker 1: terms of what's going on on other planets is a
55:58
Speaker 1: great way to think about with unique on Earth, what's
56:00
Speaker 1: special on Earth, what's common on Earth? And so really
56:03
Speaker 1: we we can learn a lot about ourselves and so
56:05
Speaker 1: um I learned a lot of reading your book. I
56:07
Speaker 1: really enjoyed it, and thanks very much for coming on
56:09
Speaker 1: the program and answering all of our naive questions. Yeah,
56:12
Speaker 1: the great questions. I love that well, Thanks very much,
56:14
Speaker 1: and I encourage all our listeners to check out the
56:16
Speaker 1: book again. It's called The Zoologist Guide to the Galaxy
56:20
Speaker 1: and the author is Dr Arik Kirshenbaum. Thanks very much
56:23
Speaker 1: for joining us today. Thanks for listening, and remember that
56:33
Speaker 1: Daniel and Jorge Explain the Universe is a production of
56:36
Speaker 1: I Heart Radio. For more podcast for my Heart Radio,
56:39
Speaker 1: visit the I Heart Radio app, Apple Podcasts, or wherever
56:43
Speaker 1: you listen to your favorite shows.