evolution
oracknows | April 14, 2010With all the anti-vaccine nonsense going on and my feeling the obligation to fire a broadside at "America's doctor," there was a tasty bit of woo that totally escaped my attention from an old "friend" of the blog. Actually, he's an old "friend" of many skeptical blogs, both here on ScienceBlogs and around the blogosphere. In fact, it's a man so steeped in only the finest quantum woo that I once coined a name for it: Choprawoo.
Yes, we're talkin' Deepak "Quantum Consciousness" Chopra! He's back and woo-ier than ever in--where else?--that repository of woo, quackery, and anti-vaccine lunacy,…
laelaps | April 13, 2010
A red panda (Ailurus fulgens, left, photographed at the Bronx Zoo) and a giant panda (Ailuropoda melanoleuca, right, photographed at the National Zoo).
As the paleontologist Stephen Jay Gould observed in one of his most famous essays, the thumbs of giant pandas (Ailuropoda melanoleuca) are nothing at all like the large digits on our own hands. Their accessory "thumbs", visible on the surface as a differentiated part of the pad on the "palm" of the hand, are modified sesamoid bones derived from the wrist. They are jury-rigged bits of anatomy which cast nature as an "excellent tinkerer, not…
clock | April 12, 2010Whenever I read a paper from Karl-Arne Stokkan's lab, and I have read every one of them, no matter how dense the scientese language I always start imagining them running around the cold, dark Arctic, wielding enormous butterfly nets, looking for and catching reindeer (or ptarmigans, whichever animal the paper is about) to do their research.
If I was not so averse to cold, I'd think this would be the best career in science ever!
It is no surprise that their latest paper - A Circadian Clock Is Not Required in an Arctic Mammal (press release) - was widely covered by the media, both…
laelaps | April 12, 2010
An African wild dog (Lycaon pictus, left) compared to a spotted hyena (Crocuta crocuta, right). Both photographed at the Bronx Zoo.
It never fails. Whenever I visit a zoo's African wild dog exhibit someone inevitably asks "Are those hyenas?", and when I visit spotted hyena enclosures I often hear the question "Are those dogs?" These carnivores, known to scientists as Lycaon pictus and Crocuta crocuta (respectively), are only distant cousins, but the vague similarities shared between them often cause people to confuse one with the other.
There are a few quick and dirty ways to tell them…
cagapakis | April 10, 2010My two great thesis project loves are hydrogen and symbiosis, and as such, the recent news of a multicellular organism that lives in a completely oxygen free environment and gets its energy from hydrogenosomes instead of mitochondria is totally fascinating.
Hydrogenosomes are organelles that are evolutionarily related to mitochondria. Mitochondria generate energy for the cell by transferring electrons pulled off of sugars molecules to oxygen (this is why we breathe oxygen). The energy from this electron motion is transferred to the production of ATP, the energy currency of the cell, through…
laelaps | April 9, 2010
Now that the details about Australopithecus sediba have been published, I am faced with an important question - how am I going to fit the new hominin into Written in Stone?
When I started composing Written in Stone I was determined to make it as up-to-date as possible. This was not only out of a concern for accuracy, but also stemmed from a desire to present the public with some discoveries that they may not have heard about before. Given that new paleontological papers are being published every week, however, I have often been faced with the question of how to incorporate interesting new…
drorzel | April 9, 2010The National Science Board made a deeply regrettable decision to omit questions on evolution and the Big Bang from the Science and Engineering Indicators report for 2010. As you might expect, this has stirred up some controversy.
I wasn't surprised to learn this, as I had already noticed the omission a couple of months ago, when I updated the slides for my talk on public communication of science-- the figure showing survey data in the current talk doesn't include those questions, while the original version has them in there. I noticed it, and thought it was a little odd, but it had no effect…
grrlscientist | April 8, 2010tags: evolutionary biology, behavioral ecology, molecular ecology, personality, novelty seeking, exploratory behavior, dopamine receptor, dopamine receptor D4 gene, DRD4 gene polymorphism, ornithology, birds, Great Tit, Parus major, researchblogging.org,peer-reviewed research, peer-reviewed paper
Bold or cautious? Individuals with a particular gene variant are very curious --
but only in some populations.
Image: Henk Dikkers.
Research suggests that personality variations are heritable in humans and other animal species, and there are many hypotheses as to why differences in personality…
laelaps | April 8, 2010
A diagram of how the skeletons of Australopithecus sediba came to be preserved in the Malapa cave deposit. From Dirks et al, 2010.
A little less than two million years ago, in what is now South Africa, a torrential downpour washed the bodies of two humans into the deep recesses of a cave. Just how their remains came to be in the cave in the first place is a mystery. Perhaps they fell in through the gaping hole in the cave roof just as hyenas, saber-toothed cats, horses, and other animals had, but, however the humans entered the cave, their bones ultimately came to rest in a natural bowl…
laelaps | April 5, 2010According to multiple reports released yesterday, scientists will announce the discovery of a new species of two-million-year-old hominin this week. Do you know what that means? That's right; writers are breaking out the pop-sci boilerplate to tell us all about the new "missing link." To paraphrase what I have seen in the headlines alone, the find is the "missing link which will shed new light on human evolution and rewrite what we thought we knew about our history."
I don't believe the hype, but I can only speculate on the actual significance of the specimens in question. According to the…
grrlscientist | April 4, 2010tags: Birdbooker Report, bird books, animal books, natural history books, ecology books
Books to the ceiling,
Books to the sky,
My piles of books is a mile high.
How I love them! How I need them!
I'll have a long beard by the time I read them.
~ Arnold Lobel [1933-1987] author of many popular children's books.
The Birdbooker Report is a special weekly report of a wide variety of science, nature and behavior books that currently are, or soon will be available for purchase. This report is written by one of my Seattle birding pals and book collector, Ian "Birdbooker" Paulsen, and is edited…
cwilcox | April 2, 2010... over at Beetles in the Bush. Go read it! Now!
Next month's carnival will be over at Evolution: Education and Outreach. Submit now through this handy-dandy little form!
mikethemadbiologist | April 2, 2010The Smithsonian recently revamped its exhibit on human evolution, and the brand new Hall of Human Origins is definitely worth seeing. Unlike exhibits from the Small era, there is no equivocation here: humans evolved over millions of years from primates. Period. There's no ambiguity, no attempt to please theopolitical conservatives. It's also very aesthetically pleasing--the bronze statues of various hominid ancestors are amazing. If the rest of the planned renovations hit this mark, the Smithsonian will look amazing in a few years.
The exhibit also is pitched at different levels, and…
ddobbs | April 1, 2010
After I wrote in my Atlantic article about getting my serotonin transporter gene assayed (which revealed that I carry that gene's apparently more plastic short-short form), I started getting a lot of email â several a week â from readers asking how to have their SERT gene tested. This led to an interesting hunt.
It was a hard question to answer. I couldn't just tell people to do what I did, for a psychiatric researcher/MD I'd known for years, who specializes in depression and serotonin, had done mine as a sort of favor to science and journalism. That researcher also stood by, had I needed…
awild | March 31, 2010
Leptomyrmex darlingtoni, Australia
A big day for ant evolution! The Ant Tree of Life research group (AToL) has published their dolichoderine phylogeny in the journal Systematic Biology.
Dolichoderines are one of the big ant subfamilies, comprising just under ten percent of the world's ant species. These are dominant, conspicuous ants noted for having ditched the heavy ancestral ant sting and armor in favor of speed, agility, and refined chemical weaponry. Most dolichoderines live in large colonies with extensive trail networks, and they fuel their frenetic lifestyle through copious…
pharyngula | March 31, 2010This is a nicely done lecture on design flaws in our anatomy and physiology, to refute claims of intelligent design.
Part 2 Part 3
I know exactly how creationists will reply, though, since I've heard it often enough. She's making a theological argument, they'll say, claiming to know God's intent and making an assumption of his goals. It will be a restatement of the old chestnut, "God works in mysterious ways."
However, that's not the argument here. Imperfections and sub-optimal properties are an outcome of evolutionary theory; this is a positive argument that observations of the world best…
laelaps | March 31, 2010
A grey mouse lemur (Microcebus murinus). Image from Wikipedia.
Charles Darwin's visit to the Galapagos Archipelago has been celebrated time and again for its influence on his evolutionary thoughts, but I have to wonder what would have happened if the Beagle skipped the Galapagos and visited Madagascar instead. What would Darwin have made of the animals which had been evolving in splendid isolation on the African island? Would "Darwin's lemurs", rather than Darwin's finches, be among the most recognizable icons of evolution?
Answers to such questions are beyond our grasp, but the diverse…
grrlscientist | March 30, 2010tags: evolution, evolutionary biology, UV light, flight, dinosaur, dromaeosaur, theropods, Microraptor gui, paleontology, fossils, birds, researchblogging.org,peer-reviewed research, peer-reviewed paper, journal club
Figure 1. The holotype of Microraptor gui, IVPP V 13352 under normal light. This shows the preserved feathers (white arrow) and the 'halo' around the specimen where they appear to be absent (black arrows). Scale bar at 5 cm. [larger view]
DOI: 10.1371/journal.pone.0009223
It has long been known that when exposed to ultraviolent light, fossilized bones and shells -- and even…
ddobbs | March 29, 2010
Early homind skulls, from A Kansan's Guide to Science (seriously)
A couple weeks ago, the Guardian ran an article in which Oxford neurobiologist Colin Blakemore described "how the human got bigger by accident and not through evolution." Though I didn't get to it at the time, I thought that an odd headline, since evolution actually occurs when genetic accidents -- those mutation things -- grant an advantage. Now John Hawks has written a post addressing what he says is a pretty big muckup by Blakemore:
Thanks to Jerry Coyne, I encountered an interview in the Guardian with Colin Blakemore…
grrlscientist | March 29, 2010tags: evolution, evolutionary biology, behavioral ecology, animal behavior, molecular ecology, parental care, mating systems, monogamy, sexual selection, frogs, poison dart frogs, Dendrobatidae, Ranitomeya, researchblogging.org,peer-reviewed research, peer-reviewed paper, journal club
Peruvian mimic poison frog, Ranitomeya imitator.
Image: Jason Brown [larger view]
To know the breeding system is to know the genetic architecture of a species.
To know the evolution of a breeding system is to know how evolution works ..
~ Lewis & Crowe, Evolution (1955)
Genetic tests have revealed the…