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Animals can also lie to themselves?

October 17, 2019

ASU-led study reveals that like humans, crayfish talk a tough game even when they know they're outmatched

These jeans still fit.

I could do that abstract painting.

I could take that guy.

Self-deception like this seems very human. Now, thanks to a recent study led by an Arizona State University biologist, for the first time we know that it happens in the animal kingdom, too.

Crayfish are some of the most aggressive creatures on earth. They fight with big claws capable of doing real damage. But sometimes there’s not much muscle under the bravado.

“What males are doing is making as little crappy muscle as possible, which is energetically saving,” said Michael Angilletta, a biology professor in the School of Life Sciences.

It’s like buying designer knockoffs. You save a lot of money, and most people can't tell the difference. In the case of crayfish, you make a big claw without much muscle, and you put crappy muscle — that is, little tiny muscles — on it to boot. Everyone sees you wave your big claw and they presume that you’re a powerful crayfish.

Video by Ken Fagan/ASU Now

“Since they signal to each other before fighting, this is a way they can convince someone to back down without fighting,” Angilletta said. “Importantly, this only works if there’s enough crayfish out there that have big claws that are actually strong. If you accidentally fight one of those and call a bluff, you’re going to lose a claw.”

In the crayfish world, losing a claw is a disaster: It takes up to two years for a claw to regenerate. In the meantime, no one is mating with anyone who has a puny claw. 

Angilletta and his co-authors have been studying self-deception in crayfish for about 10 years. In 2006 they accidentally discovered that many crayfish with big claws were quite weak. There was about a tenfold variation.

“You would go, ‘Oh, this (pinch) is going to hurt,’ but it doesn’t hurt at all,” Angilletta said. "The question is are they not trying, or are they really not strong? And it’s repeatable from day after day with the same individuals.”

They combined mathematical modeling with an experiment to show that crayfish meet the criteria for self-deception. This approach opens up the possibility of studying self-deception in nonhuman animals, without being able to talk to them. They used 97 adult males, staging fights between 20 select crayfish and 77 opponents.

“How do we know what a crayfish would do if it knows whether it’s weak or it’s strong?” Angilletta asked. “If it knows that (it has a weak claw), it should actually be less aggressive.”

It might escalate up to the point of a fight, and then run away. The probability that a crayfish engaged in a fight depended on two factors: the relative size of its claws and the expected difference in force. How do they know how strong (or not) they are? Crayfish use claws to deter predators, defend territory and capture prey. They have a pretty good idea of how strong their own claws are. They’re also skilled at assessing their size versus an opponent’s. They can even recognize previous opponents.

So natural selection has given them an ability to detect size and identity. Given that they have those abilities, it naturally follows that they have an ability to gauge strength when knowing it will improve decisions.

“In our population of crayfish, deceptive signalers largely ignored their own strength when escalating or evading aggression,” Angilletta said. “If this benefit of heightened aggression outweighs any long-term cost, natural selection should favor individuals who escalate aggression through self-deception.”

In other words, they buy into their own bluff. Angilletta teaches a biology course on human behavior called "Why people steal, cheat, and lie," which explores the ecological and evolutionary causes of selfishness and cooperation in human societies.

“What’s new about this study is that if you’re ever in a situation where I’m lying to you, there’s also a possibility I’m selling my lie exceptionally well because I’ve convinced myself that it’s true,” he said. “That’s because of self-deception. It’s very common in psychology but it’s not really that much in biology because we’re usually thinking about nonhuman animals and we don’t know what they’re thinking. We have a hard time understanding what they know and don’t know.”

The paper was published last summer in Behavioral Ecology.

Scott Seckel

Reporter , ASU Now


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New ASU degree program to provide more nuanced understanding of disability

October 17, 2019

While making her way around the city on a recent afternoon, Arizona State University Professor Patricia Friedrich noticed something about the crosswalks.

“It was incredibly hard getting to the other side in time because of the way they were timed, which is for a particular kind of speed of mobility,” she said. “I’m 5-3 so it was a struggle, and it immediately made me think, 'What about anybody else who has differences in mobility? Anybody who’s a wheelchair user, or a child?'

“If you think about the concepts of equity and equality, everybody gets an equal amount of time, but it's not an equitable amount of time.”

Friedrich, who serves as associate dean of academic programs and faculty affairs at the New College of Interdisciplinary Arts and Sciences, is one of a trio of faculty who helped launch the new Disabilities Studies degree program this semester. Associate Professor Theresa Devine and Professor Majia Nadesan also played crucial roles.

“Now, as disability studies scholars and students, we hope to raise awareness and intervene when features of the environment — cultural, social, physical — don’t contribute to an equitable living space and living conditions for people with different abilities,” Friedrich said.

The Disabilities Studies program is one of only a few full degree programs like it, and it is open to students of all majors.

“Not only do we want to attract students who want to study disability studies exclusively, but also folks who might be interested in a concurrent degree with their particular areas of expertise — whether that’s architecture, civil engineering or teaching — because we need to forge a society where we have professionals in all different areas of expertise that have this awareness and bring it to their practice.”

Both Friedrich and Nadesan view disabilities studies through the lens of social critical theory, which means they take into account things like language and other social constructs that affect people’s perceptions of disability. Their intention is for the new degree program to do that same, by taking a humanistic approach to helping students understand the concepts of ability and disability as social constructs.

In the below Q&A, the pair share their expertise and thoughts on the subject with ASU Now.

Editor’s note: Responses have been edited for length and clarity.

Question: According to the U.S. Census Bureau, the number of people living with disabilities is expected to increase by about 21% from 2007 to 2030. Why are we seeing such a dramatic increase?

Nadesan: I think there's a lot of debate about whether incidents of conditions that make people eligible for a diagnosis of a disability are increasing or not. I am of the side of the fence that believes that there are increased incidents. For example, incidents of neurological disorders are growing in both children and adults, and that could be a function of the built environment. I see a neurologist, and she is convinced that we're poisoning ourselves (via toxic elements in the built environment) because she has seen so many more neurological problems over the course of her career. But you could make an argument that people are simply more likely to get a diagnosis because there's less stigmatization and because, through the Americans with Disabilities Act, there's legislation that would support accommodations. So there’s not 100% consensus.

Friedrich: The other potential piece is the fact that as the population ages, the likelihood that an age-related disability could develop is greater, and America has a large population of aging adults. So it's very multifaceted. And it also depends on what criteria you're using to define disability.

Q: What qualifies as a disability?

Nadesan: To be officially designated as “disabled,” it’s a whole government process that requires documentation and everything. But it depends on a lot of things.

Friedrich: When we talk about disability, we're talking about visible and invisible disabilities, but also the fact that disability can be a transient process. If you think of that aspect of it, then it'll include even more people. So it’s not just one thing, it's an intersection of many things, including gender, race, ethnicity and income, and what it means to live in the world at the intersection of all of those things. It's not an isolated cultural construct.

Q: What’s an example of an invisible disability?

Friedrich: Chronic fatigue syndromeChronic fatigue syndrome is also known as “ME,” which stands for myalgic encephalomyelitis. is an example of an invisible disability. But something that caught my attention recently in a medical school text was the language it used when talking about conversion disorder. (Conversion disorder is a mental condition in which a person has blindness, paralysis or other neurologic symptoms that cannot be explained by medical evaluation.) The text said something about the need to separate symptoms of conversion disorder from “genuine” seizures. And I thought, what kind of message are you sending to a person who is experiencing these physiological phenomena if you're saying that there is a legitimate condition and the other is imagined? So when we talk about changing the environment around disability, we need to remember to change the language that we use to refer to people’s experiences so that it is respectful of those experiences.

Nadesan: In academic theorizing, we talk about -etic and -emic perspectives; -etic is an observer perspective and -emic is the observed perspective. –Emic is much more phenomenological, it's experiential. So disability studies is a counterpart to the -etic medical perspective in that it is much more grounded in experiences of people who have disabilities and the environments that produce particular kinds of experiences of ability and disability and the complex relations therein. When I get students who have dyslexia or another disorder like it, I always say, "If you had been born 300 years ago, you wouldn't have a disability." Because the social construction of the environment that produced the possibility for that particular experience didn’t exist then. So that's what we want our students to understand; we want them to understand these components of experience and environment.

Q: What language should we use to refer to disabilities?

Friedrich: Linguistically speaking, there are three predominant ways of referring to people who experience disabilities. One is the person first: “Person with a disability” or “person living with a disability.” Another is disability first. It’s used less in certain communities than others, but I have seen self-advocates who prefer the language of disability first. (For example, disability-first language would be “an autistic person” instead of “a person with autism.”) And then there is indirect language, which does not refer to the disability directly but it's implied. And it all depends on what is most appropriate in each context, matters of self-advocacy and what people who experience disabilities themselves prefer. That’s an important point because the language we use can show the power of people living with disabilities to advocate for themselves.

Nadesan: It can become extremely complicated, this issue of labeling. Because, for example, in the autism community, there are a lot of people who argue that autism isn't a disability. That it's just another diversity. But that gets tricky because then how do you make a demand or request for accommodation? So it's very tricky ground.

Friedrich: Yeah. You have to ask things like, What request is being made by whom? In what context? For what purpose? It’s all of those reporter questions, if you will. All of the wh- questions. And that's what gives context. Rather than a universalized idea of what works. But always with this view of participation, of self-advocacy and inclusion.

Q: Why is this often a fraught topic?

Nadesan: I think the thought that you might become disabled or that somebody in your family might is so terrifying that there's a kind of psychological othering that goes on. And yet, the more experience you have, you realize that there is not a clear line between ability and disability; that line in itself is a social construction. And this “othering” thing is really a function of your own anxieties about it. People might be willing to be inclusive, but at the same time they don't really understand the fragmented nature of ability and disability. So they can be kind of intolerant. I'm hoping that as disability advocacy grows and as we grow the degree program that people will have more nuanced ideas about ability and disability. That they can see it as multifaceted and multi-spectrum and recognize that ability and disability can coincide.

Top photo courtesy of Pixabay