How the platypus lost its stomach

Ember the platypus has no stomach. But there's nothing wrong with her. No platypuses have stomachs. They're just one of a surprising number of vertebrate species that have evolutionarily jettisoned their stomachs, in favor of a straight-shot digestive tract that directly connects the throat to the intestines. Read the rest

Why 23andMe can't tell you everything about yourself (yet)

How can a mild-mannered grasshopper turn into a ferocious locust? Why are humans humans when we have share 80 percent of the same genetic material with a cow? In a fascinating long read at Aeon, David Dobbs delves into the differences between genetic change (evolution as you probably learned it in school) and genetic expression (the amazing powers of natural selection that scientists are only now starting to really understand). Read the rest

The creationists' last stand

In Texas, the same old fight: conservative Christians desperately trying to excise evolution, reproductive health and much science in general from school textbooks. [Dallas Observer via Metafilter] Read the rest

The ability to taste bitter flavors probably didn't evolve as a self-defense mechanism

From beer to coffee, bitter flavors are things that most of us have to learn to enjoy over multiple tastings. Scientists have long assumed that our ability to even taste those flavors is rooted in self-defense — a way to root out and avoid potentially poisonous plants in the diet of our hunting and gathering ancestors. But new research suggests that the ability to taste bitter flavors isn't strongly tied to hunting and gathering lifestyles, which leaves researchers at a loss for why the skill might have evolved. My hypothesis, based on experience with espresso and IPA lovers: Perhaps there's an evolutionary advantage to beverage pretentiousness. Read the rest

Where did land plants come from?

More than 90% of land plants have symbiotic relationships with fungus and those relationships seem to date back hundreds of millions of years. At Topologic Oceans, Charles Soeder explains how this fact has become a jumping off point for an interesting theory about the evolution of land plants — maybe all the plants we see in our daily land-locked lives are the result of symbiotic blending of algae and fungus, similar to the way our own cells now depend on the offspring of a bacterial invasion in order to function. Read the rest

Epic crab fight — Watch fiddler crabs duel, big claw-to-big claw

Male fiddler crabs are famous for their mismatched front claws — one great big and threatening, one eensy-weensy. (I used to use this as a metaphor for the split in my SAT scores.) But what's really interesting about this lopsided look is that it seems to serve multiple purposes. The big claw can be used to attract lady crabs — wave it around and it becomes the crabby equivalent of, "Yo! Adrian!" But the big claw can also be used as a practical weapon, where two male crabs go at each other like fancy fencers with one arm behind their backs.

And the extent to which the big claw is for looks or for violence seems to vary a lot depending on the species of fiddler crab, writes scientist John Christy. Some have a lightweight claw that's better for waving at the girls, but weaksauce in a fight. Others have a heavy, dangerous claw that's difficult to use for long-distance flirting. Christy and his team are in the process of trying to figure out what selection forces leave some crabs optimized for love and others for the battlefield. In the meantime, though, they made this awesome crab fight video, set to a stirring, John Williams-esque soundtrack.

Video Link Read the rest

Free human evolution course starts January 21

It's not too early to plan for next semester. John Hawks, a fantastic science blogger and professor of anthropology at the University of Wisconsin-Madison is offering a Coursera class on Human Evolution: Past and Future. Seems like just the thing for curious Happy Mutants! Read the rest

What's the point of monogamy?

More than a quarter of primate species form male-female pair bonds that scientists describe as "monogamous". That's much higher than the overall mammal average of 9 percent. But those statistics don't mean that humans are somehow "meant" to be monogamous. In fact, scientists are still debating — and publishing conflicting theories — on why monogamy would have evolved at all. Carl Zimmer has an interesting column at The New York Times looking at two recent papers, and how they fit into an ongoing scientific fascination with our own sex lives. Read the rest

Why chimpanzees don't play baseball (at least, not as well as we do)

Good news for humanity's sense of shiny special uniqueness! Sure, other animals use tools. Chimpanzees and bonobos might even have behaviors that can be classified as cultural. But those damn dirty apes still can't throw a fastball to save their lives.

Becky Lang at Discover magazine has an interesting story on this research, which centers around the biology that allows fast pitches to happen, and how we developed it, while our closest relatives did not.

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The oldest genome ever sequenced

Scientists at the University of Copenhagen sequenced the oldest genome yet — 700,000-year-old DNA from an ancient ancestor of the horse. The Nature Podcast explains why doing this is valuable (and, no, it's not about creating a cloned ancient horse park) and how you go about sequencing such elderly, and thus degraded, DNA. Read the rest

Blunders of Genius: interesting errors by Darwin, Pauling, and Einstein

History has shown us that even some of the greatest scientific luminaries, towering figures such as the naturalist Charles Darwin, the twice-Nobel-Laureate chemist Linus Pauling, and the embodiment of genius — Albert Einstein — have made some serious blunders.

Duck penises: The saga continues

As we all know by now, ducks have penises. Rather epic penises, in fact. Chickens, though, are penis-less. In fact, most birds don't have them. In an important update in duck sex news, Ed Yong follows the work of several scientists who are trying to better understand how genitals evolve and why they differ so much between species and genuses. Bonus new fact: A dissected goose penis looks surprisingly like a less-colorful Man-O-War jellyfish. Read the rest

Evolution doesn't like you

Sure, you've got those great opposable thumbs, complex culture, and the ability to walk on two legs. But don't let those facts lull you into thinking that evolution is on your side. It's not. It's not really on anybody's side. Which is why the same process that produces super-smart, super-creative apes (like us) is also responsible for helping cockroaches evade our attempts to murder them. Read the rest

How atheists find meaning and joy in nature

There doesn't have to be a pre-ordained meaning to the universe in order for it to mean something. That's one of the fun things about being human — we get to make meaning for ourselves. With that in mind, please read this lovely essay by Brian Switek about finding wonder and joy in the oft-denigrated idea of being "just" a product of time and chance. Read the rest

Centipede is beautiful, crazy

Entomologist Piotr Naskrecki found this fantastic centipede hiding under the smushy bark of a fallen log in Mozambique. You can see more photographs of it, and read more about its discovery at his blog, The Smaller Majority.

What makes this centipede particularly interesting (besides that great handlebar moustache it's sporting) is the long, fuchsia appendages on its rear end, each one topped with a feathery, yellow bit, like a flag on a pole. According to Naskrecki, nobody knows what those appendages are for. They seem to have evolved from the animal's rear-most legs, but their function is a total mystery.

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Why music makes us all verklempt (or angry, or wistful, or ...)

It could just be cultural connections that make us identify one song as happy and another as sad. But, explains Joe Hanson, there's evidence that our emotional connections to music are more universal than that.

In this video about evolution, music, and smooshy feelings, Hanson describes a study that asked participants to create short lines of music that matched specific emotions. The results were surprisingly similar, whether the participants were Americans, or people from an isolated village in Cambodia. Read the rest

Baby humans are premature, fetal apes

My dad calls the first few months of a baby's life "the necessary larval stage". I've heard other people refer to it as "the fourth trimester". Basically, newborn human babies are pretty useless, as far as baby animals go. This is especially true in comparison to baby apes, who come out of the womb at a much higher level of development. Scientific American has an excerpt from an upcoming book by Chip Walter that talks about this fact and its connection to two key moments in human evolution — the development of bigger brains (and thus, bigger heads) and walking upright (which has the side effect of creating a narrower birth canal). Read the rest

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