What is a species? That's not a simple question.
And it's even harder to answer after you've had a few.
Intrepid science journalist Charles Q. Choi takes inspiration from both the Drunk History series of videos and a really awful lot of whiskey to try and help you better understand a scientific concept (and also the finer points of orc biology). This was an idea I had, which came together with the help of several science journalist friends during the Science Online conference back in January. I'm still impressed with how accurate Charles was on the science while in that state. I can't speak to the Tolkien mythology.
Video Link (Note: This seems to play softly on some computers. If you're having trouble hearing it, plug in headphones or turn up your speakers.)
Thanks to Rose Eveleth, Colin Schultz, and Jennifer Honn — whose work on editing and producing this video was invaluable. Also thanks to John Rennie, Steve Ashley, Olivia Koski, Maki Naro, and Stephen Granade — whose input and assistance made this possible. And, of course, special thanks to Charles, who really was fully recovered by the next morning.
Image: Orc, a Creative Commons Attribution (2.0) image from ton's photostream Read the rest
Species that lack significant levels of genetic diversity have a big problem. And it's not just about ending up with tiger and kiwi bird versions of Cletus the Slack-Jawed Yokel. Beyond the risk of inbreeding, genetic diversity supplies the tools that help a species adapt to change
. If there's not enough of it, then the species is more likely to die out when subjected to stressful conditions ... like, say, climate change. Read the rest
It's a small squid world, after all
. A recent study shows that giant squid from all around the globe have remarkably low levels of genetic diversity — essentially, writes Tina Hesman Saey, they're all more closely related than scientists previously thought. Giant squid, as it turns out, are a single species, traveling, living, and breeding all around the planet. Read the rest
Events like this make an excellent case study for palaeozoologist Darren Naish's argument that we need to find a new nickname for dromaeosaurids—one that is not already being used by a significantly less terrifying class of animals. "Hey everybody, let's go to the Spring Raptor Release!" is kind of the "Let's eat, Grandma!" of species classification.
Via Laelaps Read the rest
Meet Brookesia micra, one of four newly identified species of ultra-small chameleons that live in Madagascar.
Never let it be said that reptiles can't be totally cute.
Submitterated by Dr. Sideshow and lecti. Read the rest
The Australian blacktip shark lives in tropical waters. The common blacktip shark prefers its water subtropical and temperate. Because of the difference in habitat, these two animals have become separate subspecies with distinct physical differences.
However, there are some places where their habitats overlap. And here, along the eastern coast of Australia, there is interspecies nookie. And hybrid baby sharks.
Now, none of that is particularly shocking. Hybrid zones, where the habitats of two genetically compatible species overlap, aren't ridiculously common, but scientists have documented quite a few. What makes this finding interesting is that the two species and their hybrid have been genetically documented. Hybrid zones can be fuzzy places. What happens there calls into question how sure we can be that that what we call species really are all that different from one another.
What makes this study interesting is that researchers actually performed genetic testing on sharks caught in the hybrid zone. They found distinct genetic differences between the blacktip and Australian blacktip sharks, especially in their mitochondrial DNA. And the hybrids were identified based on genetics as well. That's something that's a lot more rare in the study of wild hybrids. The information gathered here could end up having a lot to teach us about how evolution happens and what speciation really means.
Via Mo Costandi Read the rest