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Tag: "predation" at biology news

Mule deer moms rescue other fawns

...a result, whitetail fawns suffer considerably more predation during the first months of life than do mule deer fawns." Mule deer may have developed a more effective aggressive defence because they rely on fighting to protect themselves against predators year-round, while whitetails and many other species re...

Amphibians in losing race with environmental change

... communally or congregate socially, often to avoid predation or improve resource use. But global warming has caused higher levels of certain infectious diseases of some amphibians, and it spreads more easily in closely connected communities. "Although relatively rapid evolution may occur within some amphibi...

Global survey of lizards reveals greater abundance of animals on islands than on mainland ecosystems

...hat islands?limited areas and isolation can reduce predation and competition pressures. As a result, island animals were able to reach exceptionally high densities. In their study, Jetz and Buckley confirmed that reduced numbers of predators and competitors accompany high lizard densities on islands across...

Why do oysters choose to live where they could be eaten?

...earch shows that oyster larvae are willing to risk predation by adult oysters to cash in on the benefits accrued by spending the remainder of their lives among a large number of their species." Tamburri worked with UCLA researcher Drs. Richard K. Zimmer and Cheryl Ann Zimmer to examine this apparent paradox...

Tracking sperm whales and jumbo squid

.... According to one estimate, worldwide sperm whale predation on squid may exceed 100 million metric tons a year...e propose that jumbo squid are more susceptible to predation while they are recovering at depth immediately after a deep nighttime dive," he explained. In pre...

Bats prey on nocturnally migrating songbirds

... ONE ?shows that migration at night is not without predation risk for passerines. A unique creature is indeed capable of exploiting the formidable food source represented by the billions of high-flying, Eurasian songbirds which engage twice a year into long-distance, north-south or south-north nocturnal move...

Long-lived deep-sea fishes imperiled by technology, overfishing

...duces thousands of eggs ?most of which die through predation or starvation. "One of the things we need to know more about is how the fish larvae get transported," Heppell said. "We don't know whether fish from different seamounts are genetically distinct or whether larvae from one seamount end up populating...

Overfishing large sharks impacts entire marine ecosystem, shrinks shellfish supply

...s century-old bay scallop fishery. "Increased predation by cownose rays also may inhibit recovery of oysters and clams from the effects of overexploitation, disease, habitat destruction, and pollution, which already have depressed these species," says Peterson, noting shellfish declines in areas occupied ...

Salmon farms kill wild fish, study shows

...did not include the secondary effects of increased predation on infected fish." "The debate is over," said study co-author Alexandra Morton, a biologist with the Raincoast Research Society. "This paper brings our understanding of farm-origin sea lice and Pacific wild salmon to the point where we know there i...

Theory of oscillations may explain biological mysteries

...llate in synchrony because of interactions such as predation and competition. Such synchronization can have far-reaching effects. Vandermeer suggests that several well-known biological conundrums, such as the higher-than-expected diversity of plankton in aquatic ecosystems, may be explained this way. Physicis...

Hundreds of thousands of viral species present in the world's oceans

...ic material and moderate their communities through predation and parasitism. Despite their small size, they are astoundingly abundant with about as many of them in a bucket full of seawater as there are humans on the planet. As a result, they can have a huge impact ecologically. In a new study published onli...

Scientist's persistence sheds light on marine science riddle

...s often don't reach an island, but competition and predation in the deep sea can be intense. A lot more study needs to be done on the relative importance of these factors, but clearly resource limitation is a key factor in the evolution of size." ...

Does natural selection drive the evolution of cancer?

... the tumor cells that develop defenses against the predation are the ones that survive and reproduce. An example of parasitism in the tumor environment can be seen in angiogenesis, in which a subset of tumor cells send chemical signals to stimulate the host to generate new blood vessels to supply the tumor...

New moth variety disarms plants guarded by selenium

... serve a defensive function against herbivory, the predation of plants by animals. In their new work, the researchers showed that the selenium in the hyperaccumulator plant species known as prince's plume (Stanleya pinnata) protects it from caterpillar herbivory both by deterring feeding and by causing tox...

Too mellow for our predatory world

...r behaviour and endocrine stress response to novel predation threats. Scientists from the Max Planck Institute ...835. In marine iguanas living with an intermediate predation risk, it was only the act of being captured that led to increased concentrations of corticosterone, ...

Cougar predation key to ecosystem health

...iparian habitats and biodiversity may require both predation on these herbivores as well as the fear of predation to further affect their behavior, the researchers concluded. Ripple and Beschta considered ot...

Tyrannosaur survivorship -- tough times for teens

...large mammals. High newborn mortality rates due to predation alone subside once a threshold size is reached and it appears that such a threshold was reached by age two in Albertosaurus sarcophagus, say the research team. The mortality rates remained low until about the 13th year of life, at which point they re...

Time of day tempers tadpoles' response to predators

...t prey adjust their activity levels in response to predation risk, but new research by a University of Michigan... tadpoles, like many other aquatic animals, assess predation risk indirectly by sensing chemicals released by their predators into the water," Fraker said. Typic...

Insect predation sheds light on food web recovery after the dinosaur extinction

...tion, for 800,000 years, there was very low insect predation and plant diversity. We know that 9 million years ...me species found throughout the Paleocene. Insect predation was low as well. In sharp contrast, the team also found two unusual early Paleocene sites. Th...

How marine reserves are giving coral reefs a helping hand

...t grouper to swallow. This 'escape' from a risk of predation means that most reserves are unlikely to reduce the amount of grazing even afterthe number of predators rises." Peter added, "Diving in the Exuma Cays Land and Sea Park was fun because a large number of sharks turned up to watch us work. Sharks have...

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