Many palaeobiological analyses have concluded that modern birds (Neornithes) radiated no earlier than the Maastrichtian, whereas molecular clock studies have argued for a much earlier origination. Here, we assess the quality of the fossil record of Mesozoic avian species, using a recently proposed character completeness metric which calculates the percentage of phylogenetic characters that can […]
Posts Tagged ‘Russel T Sajeev’
The Completeness of the Fossil Record of Mesozoic Birds: Implications for Early Avian Evolution
Scientists reassemble the backbone of life with a particle accelerator synchrotron X-rays
Scientists have been able to reconstruct, for the first time, the intricate three-dimensional structure of the backbone of early tetrapods, the earliest four-legged animals. High-energy X-rays and a new data extraction protocol allowed the researchers to reconstruct the backbones of the 360 million year old fossils in exceptional detail and shed new light on how […]
Low Extinction Rates Made California a Refuge for Diverse Plant Species
The remarkable diversity of California’s plant life is largely the result of low extinction rates over the past 45 million years, according to a new study published in the journal Evolution. Although many new species have evolved in California, the rate at which plant lineages gave rise to new species has not been notably higher […]
Study Reveals Jurassic Ecosystems Were Similar to Modern: Animals Flourish Among Lush Plants
Typically researchers count the number of animal species discovered in a region to determine how many different types of animals once lived there. Scientists call that a measure of faunal richness. Myers took a different approach. Using a traditional method typically used to estimate carbon dioxide in the ancient atmosphere, Myers instead applied it to […]
Giant Fossil Predator Provides Insights Into the Rise of Modern Marine Ecosystem Structures
An international team of scientists has described a fossil marine predator measuring 8.6 meters in length (about 28 feet) recovered from the Nevada desert in 2010 as representing the first top predator in marine food chains feeding on prey similar to its own size. A paper with their description will appear the week of Jan. […]
Sea Temperatures Less Sensitive to CO2 13 Million Years Ago
In the modern global climate, higher levels of carbon dioxide (CO2) in the atmosphere are associated with rising ocean temperatures. But the seas were not always so sensitive to this CO2 “forcing,” according to a new report. Around 5 to 13 million years ago, oceans were warmer than they are today — even though atmospheric […]
Fossil scars capture dinosaur headbutts
With domed heads and thick, bony skull protuberances, pachycephalosaurids are well known by seven-year-olds and palaeontologists alike. The dinosaurs are thought to have used their thick domes to headbutt each other, perhaps as part of courtship behaviour. But whereas children recreating these vicious displays simply ram plastic models of the animals together in a straight […]
Origin of Photosynthesis Revealed by a ‘Living Fossil’
Recently, the complete genome of a glaucophyte alga (Cyanophora paradoxa) has been unraveled by an international consortium led by Dr. Debashish Bhattacharya from Rutgers University (USA). From the University of Freiburg, Dr. Stefan Rensing and Aikaterini Symeonidi (Faculty of Biology), contributed to the analysis of the genome by performing classification and phylogenomic analyses of the […]
Asteroid impact Wiped out the ‘Obamadon’
The asteroid collision widely thought to have killed the dinosaurs also led to extreme devastation among snake and lizard species, according to new research — including the extinction of a newly identified lizard Yale and Harvard scientists have named Obamadon gracilis. “The asteroid event is typically thought of as affecting the dinosaurs primarily,” said Nicholas […]
Research Reveals New Information On the Evolution of Dinosaur Senses
An international team of scientists, including PhD student Stephan Lautenschlager and Dr Emily Rayfield of the University of Bristol, found that the senses of smell, hearing and balance were well developed in therizinosaurs and might have affected or benefited from an enlarged forebrain. These findings came as a surprise to the researchers as exceptional sensory […]