What if we stopped seeing females (of every species) as passive and instead welcomed the extraordinary diversity of sexuality? Through tales of same-sex bird couples, sexually transformative fish and unexpectedly promiscuous chimps, zoologist Lucy Cooke invites us to embrace the "genderless continuum" of females in nature, ditching archaic sexual stereotypes and offering a path to better understanding our natural world -- and each other. (This conversation, hosted by TED science curator David Biello, was part of an exclusive TED Membership event. Visit ted.com/membership to become a TED Member.)

It is absolutely a privilege and a pleasure to introduce our special guest for the day.

She's a zoologist, an intrepid explorer, and a lover of sloths, as many of you will know from having seen her TED Talk.

She's here to talk to us about how we've been getting females all wrong, as detailed in her amazing new book entitled Bitch.

I personally can't recommend this book highly enough.

If you ever wanted to know about the weird, wild stuff going on in the animal world, this, this, I'm gonna pick it up again, is the book for you.

Here to share some of that with you, it is my great pleasure to introduce my friend, Lucy Cook.

Hello there, hello everyone All over the world.

Sorry, my dog is literally on cue, just started barking at the door.

Well, I'm here to talk to you today about female animals because being female has never been more scrutinised or politicised.

So what can the rest of the animal kingdom teach us about what it means to be female?

Well, today I'm going to introduce you to 3 females that force us to reconsider traditional binary expectations of bodies, brains, biology, and behavior.

Now, Humans share almost 90% of our DNA with this lesser known great ape.

But bonobos have equal claim to be our closest relative.

But it's always chimpanzees that are used as the model for human ancestry.

Chimp and bonobo society couldn't be more different, however, where chimps are patriarchal and warlike.

The female or the male bonobo is bigger than the female, as is the case with chimpanzees.

But this physical dominance doesn't translate as power because the females have formed an incredibly strong sisterhood, which usurps the male power.

Now, this sisterhood is established and maintained by sex.

In particular, sex that's referred to in scientific circles as genitogenital rubbing.

And this GG rubbing prevents females who would otherwise probably be competitive with 1 another over resources to instead form strong alliances.

And in that way, these alliances allow them to dominate males.

So you could say that the bonobo female has evolved to overthrow the patriarchy through ecstatic same-sex frottage, which is of course 1 way of doing it.

But Bonobos are just 1 of the many females that defy the deterministic sex roles laid out by Charles Darwin in his theory of sexual selection in

Females, as Darwin saw it, were passive, coy and submissive, whereas males were active, ardent, competitive and the dominant drivers of evolutionary change.

Now, these Victorian sexual stereotypes have hung about in the scientific realm for far longer than they should thanks to Darwin's reputation.

But females like the bonobo are teaching us that sex roles aren't actually fixed as Darwin saw them, instead they're plastic and they're shaped by the peculiar interaction of genes and the environment.

Bonobos teach us that sexuality is also flexible.

All bonobos are considered to be bisexual.

A great example of that is the garden mole, because the female mole's gonads are described as ovotestes.

So they are part ovarian tissue, but part testicular tissue.

Now, during the short breeding season, the ovarian side produces eggs, as you would expect, but outside of the breeding season, the testicular tissue swells and pumps out lots of testosterone which makes the female mole extremely efficient at digging and and very aggressive when it comes to guarding her worm larder and her pups.

So this gonadal fluidity is something of anomaly, and was considered something of anomaly when it was discovered in mammals for whom sex is thought of as being a static binary that's established during embryonic development because the embryonic foetus starts out as sexually neutral And the pathway to being male or being female to developing ovaries or developing testes was long thought to have been triggered by basically an on-off switch, which in the case of humans is the presence or absence of the SRY gene.

But the idea that sexual determination is an either or situation and that these 2 pathways to being either an ovary or a testes, a linear and distinct is woefully simplistic, we now understand.

The sex determination system really owes more to anarchy than it does to order, because these 2 pathways, becoming a testes or, or for the gonad to become either a testes or an ovary are neither linear nor distinct.

And what's more, they're governed by basically the same

sex determining genes which are scattered throughout the genome.

Now these androgynous set of sex-determining genes have the ability to create either an ovary or a testes, but which depends on a complex system of intergene negotiation.

And of this system, mutual antagonism is also a critical feature.

So some genes will be actively creating a testes, but at the same time, they're also actively suppressing an ovary.

Now this antagonism continues into adulthood.

There was a recent study on mice that found that in adult mice, the existence of testicular cells required the active suppression of ovarian cells.

And this was very shocking to the scientific community to discover the instability of this system.

I mean, you know, sexual determination is pretty fundamental for sexually reproducing animals, so you sort of would expect the system to be a little bit less leaky, as it were.

Well, no, actually, because the mole helps us understand why this systemic plasticity is in fact an evolutionary winner.

Because when geneticists came to decode the mole genome just a couple of years ago, they found that the female's gonadal fluidity was the result of just 2 mutations of the regulation of 2 of the sex determining genes.

So such mutations might be considered a pathology in some animals, humans included, but if the mole didn't have them, then it wouldn't have been able to adapt to its life underground.

So this makes us realize variation is the grit that drives evolution forward.

And the antagonistic nature of the sex determination system with its ongoing battle for primacy between the male and female pathways may seem dangerously unstable, but viewed another way, its ability to create novel variation for natural selection to act upon could be considered a great advantage.

So other more ancestral vertebrates show even greater sexual plasticity due to this antagonistic system, and no more so than those that are actually able to switch sex during their lifetime.

Now, these sequential hermaphrodites are common in the vast blue deserts of the ocean where it's handy if you can change your sex to complement whatever member of the opposite, whatever member of your species you actually bump into.

And there are about 500 species of fish that have the ability to change sex.

Some do it as often as several times a day, but the most famous is the anemone fish, the star of Finding Nemo.

Now these fish live in anemones, and there's generally a dominant female and her male partner, and often a couple of undeveloped prepubescent, let's say, they're not sexually developed males.

And what happens is if you take the dominant female out of the situation, if she's nabbed by a barracuda, say, then the male will transition into becoming the female.

And 1 of the immature males will will go through sexual maturity and become her mate, which means, of course, that a biologically accurate version of Finding Nemo, which saw little Nemo lose his mother and then go on a massive adventure before being reunited with his father at the end of the film, would have seen Nemo's father transition into his mother and then start having sex with him, which would have been a slightly less family-friendly film.

But what's really fascinating about anemone fish is when you study that change, because what happens is, as soon as the female dominant female is taken out of the situation, the male anemone fish starts to be recognised as a female by other fish and behaves as a female, but it takes up to a year for his gonads to make the change from testes to ovaries.

So what that suggests is that sex is not a unitary phenomenon and that biological sex or gonadal sex, sexuality, sexed behaviour and sexual identity are all independently regulated in this fish and perhaps other vertebrates.

We've been conditioned by Darwin to think of biological sex as a static binary with strict gendered outcomes.

But the females we've met today teaches that sex is highly complex.

And it's a highly complex set of traits whose plasticity creates the extraordinary variety that we see in nature.

And it's my belief that the time has come to ditch the sort of damaging and frankly deluded binary expectations because in nature, the female experience exists on a genderless continuum and it refuses to conform to archaic stereotypes.

And our appreciation of this fact can only really enrich our understanding of the natural world and empathy for 1 another as humans.

standing in for the whole other audience, who I'm sure are wildly applauding.

I'm just really thrilled that Kobe has now gone to sleep beside me, because that could have got really, really tricky.

It is not an official Zoom meeting until there's a pet or a child.

So crazy stuff about the clownfish and bonobos and everything else.

But From reading your book, there's 1 particular story that stood out to me.

Tell us about how you stole a lion's girlfriend.

Yeah, so this was the sort of the beginning of my journey for questioning the stereotypes that I was taught at university.

My tutor was Richard Dawkins, who some of you probably have heard of.

And he taught me these Darwinian stereotypes that females were passive, coy and monogamous, and males were the promiscuous ones that had all the fun, basically.

I had no reason to question what I was taught, other than the fact that it didn't really appeal to me as an egg-making student of evolution.

And then it cut to about 20 years later, and I was making a series about animal communication in the Serengeti, and we were trying to start a conversation with a lion, which is actually possible.

So all you need is a little speaker and the sound of a lion's roar.

Which, by the way, the sound of a lion's roar is nothing like the kind of majestic roar of the MGM movies.

So, because the lion doesn't sound enough like a lion, but they used a different sound.

But anyway, a real lion's roar sounds more like, ooh, ooh.

It's more like the sound that Boris Johnson would make looking for cheese at midnight.

Anyway, so I thought it just seemed the most ludicrous thing to be doing.

We got our little speaker out, and, you know, we played this, ooh, ooh, noise.

And sure enough, in the background, we heard, ooh, ooh.

And then for about 5 minutes, we played audio ping-pong with these lions.

And eventually, 3 lions emerged from the gloom, 2 males and a female.

And when the males realized that there was nothing there that looked or smelt like a rival lion, they went off.

But the female lay in front of the Jeep and legs akimbo and pinned us to the spot for 2 whole hours.

Seifert, the German lion specialist who I was with, I was like, what's going on?

And he's like, oh, she wants to mate with us.

And I was like, well, isn't she mating with 1 of those other males that she was with?

He's like, oh yeah, yeah, don't you know the female lion is, she massively promiscuous and will mate over a hundred times with multiple males during her fertility period.

And I was like, whoa, that's not what I was taught at university.

And I was, And that sort of like started me thinking.

And I was like, oh, I wonder whether what I was taught, you know, this sort of building blocks of the evolutionary, you know, the sexual selection paradigm are actually true.

And I discovered that in the years since I went to university, which was quite some time ago, it was the late 1980s, early 90s, but since then a revolution has happened in our understanding of what it means to be female.

It's about this revolution and really sort of trying to bring to light that the pioneering scientists, some of most of whom are female, but not all.

There's plenty of male feminist scientists doing amazing work that whose work is in the book, but how and why it's taken so long for us to understand really what it means to be female.

So that suggests, and members please get your question in the Q&A, this is your chance.

You can ask about clownfish, you can ask about bonobos, You can ask about your favorite animal, and Lucy may answer.

I should explain, actually, why the female is so promiscuous.

You were probably going to ask me anyway, David.

But the thing is, we now know why the female lioness is promiscuous.

It's thanks to the work of Sarah Blaffer-Hurdy, who in the 1980s was studying langur monkeys, and she noticed that the female langurs were also soliciting sex from males outside the group.

And she was really the first scientist who, rather than sort of dismissing this awkward anomaly as exactly that, thought, well, this is interesting, I'm going to investigate this.

And what she found was that she'd actually gone to India to study infanticide in langurs, And she found that this promiscuity and the infanticide were actually linked.

And the thing is, is that, you know, male langurs are infanticidal, they'll kill females' babies.

And Sarah realized that they do this because if a male comes in and takes over a group, then he doesn't want to waste his energy raising other males' offspring.

And by killing the babies, it means the females stop lactating.

And so they're forced into their fertility period again.

And so they're ready to mate with him and have his offspring.

But the female counter strategy to this is to mate with all the males in the area.

And that way, when a male takes over a group, if he's recently mated with the female, he's unlikely to kill the babies because they may be his.

So, and in some cases, in some primates, I mean, females are having, you know, female chimpanzees, for example, have been documented having sex 50 to 60 times a day with many, many males.

I mean, it's positively exhausting, the idea of it.

But if you're a human, you might be called all sorts of derogatory names for that behavior, but actually in the animal kingdom, it's just about being assiduously maternal, as Sarah Blaffer-Hurdy points out.

So all of this suggests, as you pointed out with your story from Richard Dawkins, that our thinking is somewhat tainted, perhaps.

So to what extent is our thinking about evolution in general, tainted by these Victorian biases?

And I think that the thing is that when Darwin came to come up with his theory of sexual selection, it was 20 years after natural selection.

And he realized that natural selection couldn't explain everything that we see in nature, right?

So he was bothered particularly by the peacock's tail.

Like why would something so gaudy and flamboyant, how could that have been shaped by the utilitarian survival force of natural selection?

Because that tail surely makes it harder for the bird to fly, harder for it to hide from predators.

You know, it doesn't help with survival, right?

And he realized that actually there was a second evolutionary force.

And that was, it wasn't just the quest for survival, it was about the quest for sex.

And so he, in his theory of sexual selection, he looks to define the differences between the sexes as he saw them.

Now, Darwin was a meticulous and brilliant scientist, and his theory of evolution by natural selection is brilliant and I think probably untated by these biases as such.

But sexual selection, because it dealt with the nature of males and females, it was much more vulnerable to cultural bias.

And so he sort of infused his ideas with the cultural thinking of the time in which women didn't have an awful lot of standing.

So It's little wonder really that the female of the species came out marginalized and misunderstood like a Victorian housewife.

But then because Darwin had said it, it then hung around in the scientific realm for over a century.

And people who were studying the differences between the sexes or sexual behavior, they just saw what fitted Darwin's paradigm, or worse, just completely ignored females because the idea was that they, it was only males where the action was.

Females are just a sort of feminine footnote to the macho main event.

So it took a long time for, and really it took this sort of pioneering group of American female zoologists and evolutionary biologists and anthropologists to challenge these stereotypes starting in the 1980s.

But this sexist stain has bled a long way and we're still dealing with that today.

You know, it's proving very stubborn to wash out.

You know, just even in the language that's used in textbooks today is all males are active and they do things and females are passive, males act and females react, you know, and it's just It's not considered an even playing field at all, even today.

TED member Gordon wants to know what you think the biggest current mysteries are about sex in the animal kingdom?

Well, I tell you what, so I set out on this quest to write this book to sort of investigate sexist bias, basically, that had its roots in Victorian misogynistic culture.

And what I didn't expect was that I didn't have other types of bias.

So geographic bias and also heteronormative bias.

So, you know, we have this assumption that families are, you know, it consists of a male and a female, right?

That's, you know, and you know, in many cases that's right, but it isn't always the case.

And that heteronormative bias can trip us up.

So a good example of this is on the island of Hawaii, I went to go and investigate an albatross colony that there is there.

And these albatross have been studied for over 50 years and sort of meticulously documented by the University of Hawaii, you know, staff and zoologists.

And there'd always been this anomaly that some nests had 2 eggs.

Now, this is a sort of, it's a complete impossibility for a female albatross to lay 2 eggs.

Albatross are 1 of those birds that does sort of practice the serial monogamy and you need, you generally need 2 albatross in order to raise a chick and a female can only lay 1 egg at a time and it takes 6 months of tag teaming in order for the chick to fledge.

So these 2 eggs were an anomaly and for years there were all sorts of strange explanations as to why there'd be 2 eggs.

Anyway eventually about 5 years ago Lindsay Young who's been studying the albatross there thought well I wonder if anybody's checked to see that the albatross couples, which are identical, males and females are identical, are actually males and females.

And so she went round and took feather tests from every nest and did the DNA on it.

And to her complete shock, she found that a third of the couples were female-female couples.

So what's happening there is that this particular colony is a relatively new 1.

And with albatrosses, it's often the females that will disperse from their natal area.

And these pioneering females, you know, starting a new colony, there's a shortage of males.

So they're making the best of a tricky situation and they are basically using other albatross husbands as sperm donors and then shacking up with another female in order to raise the chicks.

So both females will lay an egg, and then what happens is just 1 generally survives and the other doesn't, because they can't physically raise 2.

So, you know, What's fascinating about this and sort of incredibly charming is that some of these females, you know, will make mate with a, you know, will partner with a female 1 season and then the next season they might meet a male and then they might partner with him from there on in.

But some of these female partnerships just work, right?

So I met this couple that have been together 17 years.

They've had 8 chicks together and 3 grandchicks and their relationship just works.

And their bond is clearly incredibly strong after every, you know, 6 months.

Um, Albatross spends 6 months as solo artists out on the wing, feeding themselves up, but they, you know, when these 2 reunite, they do all the same hilarious dances and, and do the grooming and the nuzzling that creates all the bird oxytocin that keeps that bond really strong.

So, but yeah, so they have this sort of, you know, very strong bond and they do all the same things as male and female couples would and are actually amongst the most successful.

So what that shows us is that, again, like the bonobos, it shows us the sort of flexible nature of sexuality and just the flexible nature of sex behaviour, which shouldn't be surprising because flexibility and variation have to exist in order for evolution to happen.

But yet we had this idea that somehow sex was exempt from that and sexual traits were sort of fixed and not as flexible and plastic.

I really recommend I recommend visiting as well.

it couldn't be in a more beautiful spot if it tried.

So I was I was delighted to go and investigate, I have

That couple has a sweet spot for their homestead.

So TED member Agata, if I'm saying that correctly, wants to know, You mentioned the clownfish and other fish that change sex.

Do their sexual selection strategies change as the sex of the animal changes?

Yeah, they definitely will, because they'll need to complement 1 another.

So, yeah, I mean, it's the strategies that there'll be different between different fish, you know, according to whether, you know, what the environments that they live in, you know, as in different species that go through different, different sequential hermaphrodites and, and, and, and different, you know, there'll be individual differences as well.

That will, the whole, the whole lot will be affected.

So TED member Tara wants to know, do these sex behaviors of the various animals correlate or have any link to lifespan or even the endurance of a species as a whole?

That is a really brilliant question, and well done, because I haven't...

Nobody has spotted that and asked me that yet, and I've been on tour talking about this book for a while, So I'm very impressed.

And Patricia Goarty, who is 1 of these sort of pioneering feminist biologists, who's torn down a lot of these stereotypes, she actually thinks that that has a lot to do with it.

So so really what she thinks drives, you know, so the sort of traditional idea is, is that females are chaste and choosy and males are promiscuous.

Well, she thinks that it's not, you know, biological sex isn't a crystal ball, it isn't that, but it's the environment, but it's also encounter rate.

And so that is like, you know, if you live a long time and you're going to encounter a lot of the opposite sex, you can probably be choosier.

But if you're not gonna live for very long, you're probably gonna have a strategy that requires mating indiscriminately with whatever you come across.

Patricia Goharty would give you 5 stars for that.

Well, so we've been talking a lot about sex, but there is another way that animals do things.

Can you explain what that is and why it might be important to the endurance of a species?

So, yeah, so Parthenogenesis is basically cloning, and there are a whole heap of animals, mostly microscopic spineless wonders that are capable of reproducing just by cloning.

But there are also a whole bunch of vertebrates that are able to clone themselves too.

I was kind of shocked by this because I sort of thought, oh, it's just something that, you know, aphids do, for example, which they do pretty spectacularly, by the way.

But but when I was in Hawaii, actually, to justify the air miles, I didn't didn't just investigate 1 animal because there were 2 because there was a there's a there's a there's a lizard.

Sorry, a gecko in Hawaii called the morning gecko, not morning as in day and night morning, but morning as in sad.

Although it didn't seem particularly sad to me.

It seemed like it was gonna be grinning from ear to ear because this species of gecko is all female.

So the ability to clone yourself is only females have that ability because females produce eggs and eggs are nutrient rich and they can they, you know, a sperm can't do that.

Can't there are no males that are able to clone themselves.

And these geckos have been, have sort of, you know, cloning yourself is a great way of colonizing quickly, because if you're able to do that, it's twice as effective as having 2 sexes that need to meet and combine.

And so this is sort of being called the the the paradox of sex, which is considered the queen of all questions.

Well, we were the traditional answer has been that sex exists because it creates variation, right?

And variation allows us to adapt to a new environment, but it also stops the buildup of harmful mutations that occur during copying mistakes that occur down the line.

And if you don't have sex, then you can suffer from something that sounds awful as mutational meltdown is what it's called in the scientific realm.

So these all-female species, I mean, this particular gecko, there are no males in existence.

See all Lucy Cooke transcripts on Tedtalk

What can animals teach us about sex and gender?