Discovery of new bird species in China, oldest beak shows evolution complexity
...said. "This is a mosaicpattern we see very much in vertebrate evolution - in other words, variouslineages showing both primitive and advanced features at the same time. Whatthis really shows is that early bird evolution was not linear, as many peoplehave depicted it, but rather a far more complicated 'bush' wit...Roundworm studies yield new insight into organ formation
... criticalfor the migration of a specific cell, the vertebrate counterpart may beimportant for the migration of c...ne theory is that the worm enzyme, like one of its vertebrate familymembers, snips apart a molecule called collagen that makes up the supportingstructural matrix ...Rockefeller University Scientists Receive Prestigious Awards For Cancer Research
... my career in the early days of understanding what vertebrate genes wereand how they function," Dr. Roeder said. "I first became interested in geneactivation because this process is at the center of cell growth anddifferentiation. As we become familiar with the fundamentals of how genes work,we get closer to u......r implicating T-box genes asimportant mediators in vertebrate pattern formation.With regard to evolution, the Tbx-subfamily of T-box genes are good candidatesfor key regulators of the development of paired appendages in all tetrapodes.The expression patterns strongly suggest that their function of regulating th...Researchers Find Unexpected Feature In Plankton Nervous System
...in is a white fatty sheath that coats parts of the vertebrate nervoussystem, including the long axons of nerve cells. Like insulation on an electricwire, myelin protects and speeds the electrical signal, providing a competitiveadvantage for organisms that must respond quickly to capture food or escapepredators...New Findings On Primitive Shark Contradicts Current View Of Jaw Evolution
...f the most significant evolutionary events inearly vertebrate history. Little is known about the jaw's origins,...ery removes one of the problems of deriving ajawed vertebrate from a jawless one by saying the jaw has a correspondingstructure in a lamprey, which is jawless," e...New Gene May Help Scientists Understand More About How the Body Grows
...signals that control one of the earliest stages of vertebrate development,establishment of the head-to-tail orientation. The embryonic events that Dr.Sive studies happen very early in development; in human terms, they take placewithin the first three weeks after conception--before most women even know theyare p...What Makes An Arm An Arm And A Leg A Leg
...ne that canpartially transform the upper limb of a vertebrate into a structure thatresembles its lower limb. The...rch 12 Science,open new doors to understanding how vertebrate limbs acquire their identity.Postdoctoral fellow Malcolm Logan and Clifford Tabin, professor of gene......n differentiation and axonal growth andguidance in vertebrate embryogenesis. (Development 125, 4225-4234, 1998; ...999; Science 283, 1180-1183,1999) The formation of vertebrate organs is a complex process. It is characterised bythe interaction of different cells and tissues to...Gene Orchestrates Heart Chamber Development
February 19, 1998 --Early in development, the vertebrate heart istransformed from a narrow tube into a powe...uary 19, 1999, issue of the journal Science . All vertebrate hearts have two types of chambers -- atria and ventricles,which pump blood into and away from the he...UF Researcher: New Techniques Help Reconstruct Ancient Diets
...hedepartment of geological sciences and curator of vertebrate paleontology at theUniversity of Washington's Burke Museum. "The research by MacFadden andcolleagues provides impressive quantitative evidence that permits precisestatements to be made about a partitioning by these related genera of dietaryresources ...UNC-CH Ligament-Tendon Structure Discovery May Lead To Better Treatment, Scientists Explain
...ecause no onehas been able to release fibrils from vertebrate tissue before," Dahners said."We now have pictures of fibrils that we have been able to extract from the rattail tendons. No one has ever seen these structures before either." Although the research was conducted on rat tissues it likely will ......the distributions ofterrestrial plant communities, vertebrate species habitats and land ownershipand management patterns. Michael Hamilton, director of the James San Jacinto Mountains Reserve inRiverside County, shows how NRS scientists are working with resource managersand planners to improve forest health, r...Fossil Eggshells Hold Clues To Major Animal Extinctions As Reported In Science
...fair that cost thecontinent many large terrestrial vertebrate species like none known today,including carnivorous kangaroos, 20 foot-long monitor lizards, and a hornedtortoise nearly the size of a small car. Until now, however, a fundamentalobstacle has been nailing down the actual timing of the event, largely ...Bird Dads Suffer Infidelity But Bring Up Baby
... other males. Jacanas arepractically unique among vertebrate animals, in that females pair simultaneouslywith a harem of males (a mating system called polyandry) and the males performessentially all of the care of the young. The biologists made DNA fingerprints of 465 adult and juvenile birds. Geneticfingerp...Bones of Crocodile-like Beasts Tell Tale of Global Warming
...ing at has tremendous importance. It was clearly a vertebrate fossil- our guess was a large reptile, which would have required a relatively warmclimate to survive." The fossils locked in a record of what was happening in the Arctic justas extreme volcanism around the planet was winding down. Most of the...First Complete Fossil Of Fierce Prehistoric Predator Found In South Africa
...e bodylike reptiles. The specimen will be given to vertebrate anatomists for studybefore it is prepared and mounted for display in the South African Museum inCape Town. Smith and Ward measured the skull at about 30 inches long, while the backbonewas more than 6.5 feet long and the overall length was nearly 9.75...World's Oldest Known Fossil Reptile Nests Discovered In Arizona's Petrified Forest
...irregular, trampled ground that appears to contain vertebrate tracks, Hasiotissaid. The researchers also discovered distinct tracks of phytosaurs aboutone-half mile from the nesting sites. The walls in the interior of the nests appears to have been compacteddown by the inhabitants. Contemporary croco...USGS Issues Wildlife Health Alert: Associates Virus With Salamander Die-Offs
...ion years are among the most ancient land-dwelling vertebrate animals. The international scientific community has expressed growing concern over population declines in all amphibian groups. These losses are now well documented and have occurred in a wide range of habitats, including remote and pristine areas in......ke structure that precedes the vertebral column in vertebrate embryos, signals neural cells to induce the formation of floorplate, a crucial row of cells that lies along the floor of the ventralbrain and spinal cord. This belief has come under fire recently, as new data about floor plate development cast doubt ...