In many, animal species are domesticated when humans bring them into their homes whether they want to be there or not. For example, it's mostly accepted that humans domesticated wolves, breeding them in captivity until they became the modern dogs we love today. Now, a new study of cat genetics reveals that cats just kind of hung around humans for thousands of years before they were domesticated. From Casey Smith's article in National Geographic:
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The earlier ancestors of today’s domestic cats spread from southwest Asia and into Europe as early as 4400 B.C. The cats likely started hanging around farming communities in the Fertile Crescent about 8,000 years ago, where they settled into a mutually beneficial relationship as humans’ rodent patrol.
Mice and rats were attracted to crops and other agricultural byproducts being produced by human civilizations. Cats likely followed the rodent populations and, in turn, frequently approached the human settlements.
“This is probably how the first encounter between humans and cats occurred,” says study coauthor Claudio Ottoni of the University of Leuven. “It’s not that humans took some cats and put them inside cages,” he says. Instead, people more or less allowed cats to domesticate themselves.
A second lineage, consisting of African cats that dominated Egypt, spread into the Mediterranean and most of the Old World beginning around 1500 B.C. This Egyptian cat probably had behaviors that made it attractive to humans, such as sociability and tameness.
The results suggest that prehistoric human populations probably began carrying their cats along ancient land and sea trade routes to control rodents.
Research suggests that people who do nice things for others, often at a cost for themselves, are more sexually attractive. From an evolutionary perspective, this might be because altruism indicates that a potential mate is more cooperative and caring. Evolutionary psychologists Steven Arnocky, at Nipissing University, and Pat Barclay, at the University of Guelph, conducted a fascinating study to explore whether altruistic people really do have more sexual partners. From Scientific American:
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This theory suggests that altruism may serve, in part, to convey one’s value as a mating partner, including one’s concern for others and likelihood of cooperating with future mates. Research has shown that we prefer altruistic partners, all else being equal; especially for long-term mating (the evidence for altruism being preferred in short-term mates is mixed). Not surprisingly, then, the pull to demonstrate one’s altruism can be strong. Some research has shown that men will actively compete with one another (termed competitive altruism) by making charitable donations to women. Interestingly, these charitable donations increase when the target of one’s altruism is physically attractive...
Previous findings from hunter-gatherer populations have shown that men who hunt and share meat often enjoy greater reproductive access to women. But do these links hold up in other cultural and contextual arenas, such as in contemporary North American society? To find out, we conducted a set of two studies. In our first study, undergraduate men and women completed an altruism questionnaire (involving questions like “I have donated blood”), along with a sexual history survey. Participants also completed a personality inventory, given the possibility that those with certain personality characteristics (such as being extroverted) might happen to engage in both more altruism and more sexual activity.
Craig Froehle tracks the odd convolutions of his famous illustration of how conservatives and liberals view the notion of equality. It's been simplified, expanded, twisted, tucked in and turned inside-out—and even redrawn by professional artists.
Are the worst versions the ones that bury the simple point in condescending explanation?
Or the ones that seek to subvert it entirely, in as much as stamping "THIS IS FUCKING STUPID" over it counts as subversion?
The cannier mutations contextualize it for local audiences:
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I am giddy that my little graphic has helped so many people think about the issue of equity and has spawned so many conversations in just the past few years. I’m not upset by the many way it’s been reimagined. In fact, I’m delighted, because the modifications just make it that much more useful to people.
A paper published this summer looked into over 100 times humpbacks were observed disrupting orcas who are hunting, like these humpbacks trying to save a gray whale and calf. But why do they do it? Read the rest
Trees of Life: A Visual History of Evolution by Theodore W. Pietsch Johns Hopkins University Press 2013, 376 pages, 8 x 10 x 1.1 inches (softcover) Starting at $22 Buy a copy on Amazon
The primary metaphor for visualizing evolution is as a tree. The trunk is the oldest ancestor species which branch off newer species, which branch further leaves of the newest species. Ever since Darwin, biologists have been drawing trees to attempt to capture the complexity of evolution in various domains. These evolutionary trees are not only scientifically useful, but works of art. Over the years, many approaches to the trees have been tried – some minimal, some ornate, some abstract. This tome collects the finest, most unusual, most beautiful evolutionary tree maps produced in the last 200 years. They not only inform biology, they are fantastic examples of great design.
Language Evolution Simulation is exactly that, showing words changing little by little as time passes in a tiny world with three islands. It's agent-based, which is to say that it models little computer folk interacting with one another to simulate the little mutations that add up over time.
If an agent intersects with another, selects a word from the own vocabulary and tells that. The neighborhood receives and adds that word into its vocabulary as
- Mutation of a vowel sound with 0.1 probability
- Mutation of a const sound with 0.1 probability
- Compounding with another word with 0.1 probability
- Without any mutation
There's nothing to do but watch words change, but it feels like the underpinning of a very strange computer game about culture.
I love agent-based models; check out this simulation of political cliques I made. It randomly generates several personalities, who then go around and bicker or flatter one another. It's very bland and primitive, made in Flash, and the "next turn" text is rather fiddly to click. But I've always had plans on expanding it into a more fully featured game. Read the rest
The origin of dogs is a hot topic among biologists, who've fought over whether there's a single point of origin from wolves and when and where it (or they) happened. A new study suggests the answer is twice, independently, from populations of wolves in western Europe and in east Asia. But they interbred, so most modern dogs are descended from both western and eastern groups.
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The geographic and temporal origins of dogs remain controversial. We generated genetic sequences from 59 ancient dogs and a complete (28x) genome of a late Neolithic dog (dated to ~4800 calendar years before the present) from Ireland. Our analyses revealed a deep split separating modern East Asian and Western Eurasian dogs. Surprisingly, the date of this divergence (~14,000 to 6400 years ago) occurs commensurate with, or several millennia after, the first appearance of dogs in Europe and East Asia. Additional analyses of ancient and modern mitochondrial DNA revealed a sharp discontinuity in haplotype frequencies in Europe. Combined, these results suggest that dogs may have been domesticated independently in Eastern and Western Eurasia from distinct wolf populations. East Eurasian dogs were then possibly transported to Europe with people, where they partially replaced European Paleolithic dogs.
“The avocado is highly regarded by many people as delicious and nutritious, but the most extraordinary thing about avocados may be their very existence.”
Creatures Avoiding Planks is a web toy demonstrating natural selection. Wee blobby creatures wander around avoiding floating planks, which kill on touch. If one lives long enough, it reproduces, passing on slight variations of its own movement behavior to the offspring.
Matt Ridley, author of The Red Queen and a Conservative member of the House of Lords, reflects on Richard Dawkins' groundbreaking book about evolution, The Selfish Gene, which was published 30 years ago.
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The origin of The Selfish Gene is intriguing. Dawkins revealed in the first volume of his memoirs, An Appetite for Wonder, that the idea of selfish genes was born ten years before the book was published. In 1966, the Dutch biologist Niko Tinbergen asked Dawkins, then a research assistant with a new doctorate in animal behaviour, to give some lectures in his stead. Inspired by Hamilton, Dawkins wrote in his notes (reproduced in An Appetite for Wonder): “Genes are in a sense immortal. They pass through the generations, reshuffling themselves each time they pass from parent to offspring ... Natural selection will favour those genes which build themselves a body which is most likely to succeed in handing down safely to the next generation a large number of replicas of those genes ... our basic expectation on the basis of the orthodox, neo-Darwinian theory of evolution is that Genes will be 'selfish'.”
Dawkins began writing the book in 1973, and resumed it in 1975 while on sabbatical. At the suggestion of Desmond Morris, the zoologist and author of The Naked Ape (Jonathan Cape, 1967), Dawkins showed some draft chapters to Tom Maschler of Jonathan Cape, who strongly urged that the title be changed to "The Immortal Gene." Today, Dawkins regrets not taking the advice.
Every year, like clockwork, longstanding Oklahoma legislators in the state's house and senate introduce bills that try to find a way around the prohibition on teaching Biblical Creationism in American public schools. Read the rest
In Cary Huang's evolution simulator, one first generates 1000 random geometrical beasties. Then one watches them iterate until equilibrium prevails, commanding the most successful to reproduce and decimating the failures. The measure of the monster is how far they can flop and wobble along in a simple a 2D landscape: most fail rather fast and hard.
(The game window will start out too large for the website: scroll down and click the "full screen" icon at the bottom of the window.)
In a new paper in Science (paywalled), Nicholas J. Matzke from the National University of Australia demonstrates the evolutionary connection between anti-evolution bills introduced into US state legislatures in a series of iterated attempts to ban or weaken the teaching of evolution by natural selection and to promote Biblical creationism in various guises in its stead. Read the rest