Ecology & Zoology
First the obesity problem in humans alarmed physicians and then veterinarians worried about fat cags ( and dogs) but now a team of researchers in the Virginia-Maryland Regional College of Veterinary Medicine and Virginia Tech has determined that horses are also facing serious health risks because of obesity.
Fifty-one percent of the horses evaluated during the pioneering research were determined to be overweight or obese – and may be subject to serious health problems like laminitis and hyperinsulinemia. And just like people, it appears as though the culprits are over-eating and lack of exercise.
Unlike moths and butterflies that are often brilliantly colored to warn potential predators that they carry toxins, flowers and the fruits they produce have brilliant colors to attract the attention of pollinators and frugivores who will disperse their pollen and seed, thus guaranteeing the next generation.
The appearance of flowering plants on earth about 150 million years ago had a profound effect on the evolution of many other kinds of organisms like insects, birds, and mammals, who became the pollinators and consumers of those plants, thus ensuring the continuity of both the plant and its animal partner.
Most plants and animals show changes in activity over a 24-hour cycle. Now, for the first time, researchers have shown how a plant combines signals from its internal clock with those from the environment to show a daily rhythm of growth.
Using time-lapse photography, postdoctoral researcher Kazunari Nozue, with colleagues from UC Davis and the University of Lausanne, Switzerland, found that the shoots of Arabidopsis seedlings show a spurt of growth once a day.
The timing of that growth spurt is controlled by both the plant's internal clock and by exposure to light, acting on two genes called PIF 4 and PIF 5.
At the annual meeting of the American Society of Plant Biologists in Chicago, Dr. Jorge Zavala, Sr. of the Institute for Genomic Biology at the University of Illinois, and colleagues showed that elevated CO2 may negatively impact the relationship between some plants and insects.
Elevated CO2 is considered to be a serious catalyst of global change. Its effects can be felt throughout the ecosystem, including the insect-plant food chain link. Safeguarding highly-usable crops is of great importance to many local and national economies.
An international working group under the direction of Wolfgang und Roswitha Wiltschko of Frankfurt University has now succeeded in demonstrating the presence of a magnetic sense of direction in domestic chickens.
40 years ago, Prof. Dr. Wolfgang Wiltschko was the first to prove that migrating robins use the Earth’s magnetic field to direct themselves during migration.
Their magnetic sensor showed them the course of the field lines of the Earth’s magnetic field. This produces an inclination compass that reacts to the inclination of the Earth’s magnetic field to the surface of the Earth, thus distinguishing between “pole-wards” (the side on which the field lines incline downwards) and “equator-wards” (the side on which they incline upwards).
Cooperation in animals has long been a major focus in evolutionary biology. In particular, reciprocal altruism, where helpful acts are contingent upon the likelihood of getting help in return, is especially intriguing because it is open to cheaters.
In a new study published this week Claudia Rutte and Michael Taborsky demonstrate the first evidence for generalized reciprocal cooperation in non-humans. The authors show that rats who received help in the past were more likely to help another unknown partner.
Ongoing field trials since 2002 by a team that includes 16 farmers, Cornell researchers and Cornell Cooperative Extension field crops educators in 10 counties are showing the value of on-farm research. Their results are successfully quantifying and predicting the nitrogen needs for growing corn, saving farmers money and reducing environmental impact.
"With this program, we focus on determining under what situations extra nitrogen would be good to add and when a farmer can save money by reducing fertilizer applications without impacting yield and quality," says Quirine Ketterings, associate professor of crop and soil sciences, who co-leads the research team.
Picking a mate isn’t easy—if you are a female iguana. In a study Maren Vitousek of Princeton University and colleagues found that female Galápagos marine iguanas spend a lot of energy picking a mate from a wide range of suitors – energy they could otherwise spend foraging, producing eggs, or avoiding predators.
Scientists have generally assumed that being choosy about potential mates carries low costs for females.
Fish use the threat of punishment to keep would-be jumpers in the mating queue firmly in line and the social order stable, a new study led by Australian marine scientists has found.
Their discovery, which has implications for the whole animal kingdom including humans, has been hailed by some of the world’s leading biologists as a “must read” scientific paper and published in the Proceedings of the Royal Society of London Series B.
Studying small goby fish at Lizard Island on Australia’s Great Barrier Reef, Dr Marian Wong and colleagues from the ARC Centre of Excellence for Coral Reef Studies at James Cook University and, the Biological Station of Donana, Spain, have shown the threat of expulsion from the group acts as a powerful deterrent to keep subordinate fish from challenging tho