peer-reviewed research
grrlscientist | June 7, 2007tags: researchblogging.org, archaeopteryx, dinosaurs, mammals, fossils
Archaeopteryx fossil showing the distinctive head-back death pose of many articulated fossilized birds, dinosaurs and early mammals. Archaeopteryx is an ancient feathered dinosaur. This specimen is at the Humboldt Museum, Berlin. The skull is approximately two inches long.
If you've looked at the articulated 150-million-year-old Archaeopteryx fossils, you probably have noticed that they all have a weirdly similar pose; their heads are thrown over their backs, mouths open and tail curved upwards. Scientists have been…
grrlscientist | May 30, 2007tags: cheetahs, evolution
Researchers studied 47 litters of cheetah cubs over nine years. Nearly half contained cubs from multiple fathers.
Image: Sarah Durant [larger]
DNA technology has revealed that female cheetahs, Acinonyx jubatus, often produce litters that are comprised of cubs sired by multiple fathers. This research, recently published in the Proceedings of the Royal Society B, studied cheetahs found on that part of the Seregeti in the African nation, Tanzania.
"If the cubs are genetically more variable it may allow them to adapt and evolve to different circumstances," Dada…
grrlscientist | May 17, 2007tags: Antarctica, Weddell Sea, new species, ANDEEP, zoology
The scientists said an "astonishingly diverse" collection of isopods had been discovered. This young male isopod represents one of 674 isopod species found.
Image: W. Brokeland. [larger image]
According to a paper that was recently published, scientists have found more than 700 new species of marine creatures in seas surrounding Antarctica -- seas once thought too hostile to sustain such rich biodiversity. Fabulous creatures, such as carnivorous sponges, free-swimming worms, crustaceans and molluscs, were collected.
The…
grrlscientist | May 4, 2007tags: evolution, birds, orioles, Icterus, research
"Oriole."
Image appears here with the kind permission of the photographer, Pamela Wells.
[Larger image].
I often think about differences in morphological and behavioral traits in closely-related species and wonder whether the speed and character of changes in these traits reveal anything about the evolutionary relationships between taxa. For example, in birds, both visual and auditory cues, such as plumage and song patterns, are essential for identifying members of their own species. However, these phenomena have rarely been…
grrlscientist | May 4, 2007tags: Venus flytrap, plant, biology, mechanics
A Venus flytrap lies open, waiting for an insect to set off its trap. Lakshminarayanan Mahadevan and colleagues have shown that the plant uses stored elastic energy to operate its hinged leaves.
Image: Yoel Forterre.
How does the venus flytrap accomplish what most people cannot? How does a mere plant capture live flies? The mystery of the Venus flytrap's rapid movement lies in storing and releasing elastic energy, says Lakshminarayanan Mahadevan, who is the Gordon McKay Professor of Applied Mathematics and Mechanics at Harvard University.…
grrlscientist | April 25, 2007tags: Solomon Islands Frogmouth, Rigidipenna inexpectatus, Podargus ocellatus inexpectatus, birds, birding, ornithology
Gone are the days when animals were classified to taxon based solely on bone structure (osteology), body structure (morphometrics) or behavior (ethology), or some combination of these characters. Currently, scientists have a suite of powerful tools for classifying creatures to taxon, and analyses using a combination of these methods is allowing us to come to a deeper understanding of all animal life. As a result of using these techniques, a new species of bird has been…
grrlscientist | April 13, 2007tags: researchblogging.org, Tyrannosaurus rex, dinosaurs, birds, fossils
Repeated analysis of proteins from a fossilized Tyrannosaurus rex reveal new evidence of a link between dinosaurs and birds: Of the seven reconstructed protein sequences, three were closely related to chickens.
Image: NYTimes
It was once thought impossible to obtain actual soft tissue, such as proteins, from fossils, but the impossible has happened and now, two research teams who published reports in this week's Science describe their findings: the closest relative to the fearsome Tyrannosaurus rex is .. a chicken.…
grrlscientist | April 11, 2007tags: bipolar disorder, mania, manic mouse, psychiatric research
Some of you, like me, suffer from bipolar disorder or might know someone who does, so I thought I'd take this opportunity to write a little about the creation of a mouse model to study the genetics that are thought to underlie the manic phase of bipolar disorder -- a phase that has not been well understood so far.
Bipolar disorder, or manic-depressive illness, is a psychiatric condition that affects a person's moods. Typically, a person who suffers from a classical bipolar disorder (Also known as bipolar affective disorder,…
grrlscientist | April 10, 2007tags: dog breeds, IGF1, insulin-like growth factor 1, cancer, growth disorders
One gene mutation makes all the difference in body size between a big dog and a little dog.
Image: NY Times.
There are several things that I think are amazing about dogs, Canis familiaris. First, there is a huge discrepancy in body size between different breeds -- greater than for any other mammal, in fact, and second, these vastly different dog breeds still recognize each other as being of the same species. Yet, according to a recently published research paper, this huge differential in the body size of dogs…
grrlscientist | January 23, 2007tags: Microraptor gui, microraptor, biplane, bird flight, evolution
The ancestors of modern birds are thought to have been small, feathered, dinosaurs, the theropods. One of these small feathered dinosaurs is Microraptor gui, a feathered dromaosaur that lived 125 million years ago in what is now China. According to the evidence, Microraptor gui was one of the earliest gliders. But unlike modern birds, it appears to have utilized four wings, like a biplane, because it had long and asymmetric flight feathers on both its hands and feet.
According to initial interpretations, Microraptor flew…