According to the Chinese proverb, a bird sings because it has a song, not because it has an answer. A team of French and Brazilian researchers, however, may have the answer as to how the song of Brazilian white-browed warbler has become so well-adapted to the acoustic properties of the rainforest environment.
Understanding the evolution of acoustic communication systems in animals is a hot topic in evolutionary biology and one of the main challenges is to understand how environmental pressures drive this evolution.
The human journey from Asia to the New World was interrupted by a 20,000-year layover in Beringia, a once-habitable region that today lies submerged under the icy waters of the Bering Strait.
Furthermore, the New World was colonized by approximately 1,000 to 5,000 people — a substantially higher number than the 100 or fewer individuals of previous estimates.
The developments, reported by University of Florida Genetics Institute scientists, help shape understanding of how the Americas came to be populated — not through a single expansion event that is put forth in most theories, but in three distinct stages separated by thousands of generations.
Night-time noise from aircraft or traffic can increase a person’s blood pressure even if it does not wake them, according to a new study published today in the European Heart Journal.
Scientists from Imperial College London and other European institutions monitored 140 sleeping volunteers in their homes near London Heathrow and three other major European airports.
The researchers measured the volunteers’ blood pressure remotely at 15-minute intervals and then analysed how this related to the noise recorded in the volunteers’ bedrooms.
A new species of dinosaur unearthed in Mexico is giving scientists fresh insights into the ancient history of western North America, according to an international research team led by scientists from the Utah Museum of Natural History at the University of Utah.
“To date, the dinosaur record from Mexico has been sparse,” said Terry Gates, a paleontologist with the Utah Museum of Natural History, Utah’s designated natural history museum.
The new creature — aptly dubbed Velafrons coahuilensis — was a massive plant-eater belonging to a group of duck-billed dinosaurs, or hadrosaurs.
Johns Hopkins researchers from the Whiting School of Engineering and the School of Medicine have devised a micro-scale tool - a lab on a chip - designed to mimic the chemical complexities of the brain. The system should help scientists better understand how nerve cells in the brain work together to form the nervous system.
A report on the work appears as the cover story in the February 2008 issue of the British journal Lab on a Chip.
”The chip we’ve developed will make experiments on nerve cells more simple to conduct and to control,” says Andre Levchenko, Ph.D., associate professor of biomedical engineering at the Johns Hopkins Whiting School of Engineering and faculty affiliate of the Institute for NanoBioTechnology.
Singles’ bars, classified personals and dating websites are a reflection, not only of the common human desire to find a mate, but of the sense of scarcity that seems to surround the hunt. Many people participate in dating activities in the hopes of finding that special someone, yet feel as though it is an impossible task.
However, thanks to an international team of psychologists, the solution may be closer than we think — within ourselves, to be exact.