Tag Archives: predator

UF Scientists Find State Record 87 Eggs In Largest Python From Everglades

GAINESVILLE, Fla.University of Florida researchers curating a 17-foot-7-inch Burmese python, the largest found in Florida, discovered 87 eggs in the snake, also a state record.

Scientists at the Florida Museum of Natural History on the UF campus examined the internal anatomy of the 164.5-pound snake Friday. The animal was brought to the Florida Museum from Everglades National Park as part of a long-term project with the U.S. Department of the Interior to research methods for managing the state’s invasive Burmese python problem. Following scientific investigation, the snake will be mounted for exhibition at the museum for about five years, and then returned for exhibition at Everglades National Park. (more…)

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Mice Have System to Handle Smell of Fear

Mice appear to have a specialized system for detecting and at least initially processing instinctually important smells such as those that denote predators. The finding raises a question about whether their response to those smells is hardwired.

PROVIDENCE, R.I. [Brown University] — A new study finds that mice have a distinct neural subsystem that links the nose to the brain and is associated with instinctually important smells such as those emitted by predators. That insight, published online this week in Proceedings of the National Academy of Sciences, prompts the question whether mice and other mammals have specially hardwired neural circuitry to trigger instinctive behavior in response to certain smells.

In the series of experiments and observations described in the paper, the authors found that nerve cells in the nose that express members of the gene family of trace amine-associated receptors (TAAR) have several key biological differences from the much more common and diverse neurons that express members of the olfactory receptor gene family. Those other nerve cells detect a much broader range of smells, said corresponding author Gilad Barnea, the Robert and Nancy Carney Assistant Professor of Neuroscience at Brown University. (more…)

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Recreational Fishing Brings Salt Marsh Die-Off

As recreational fishing activity has reduced predators in many of Cape Cod’s salt marsh ecosystems, Sesarma crabs have feasted on grasses, causing dramatic die-offs of the marshes, according to a new study. The researchers assessed the “trophic cascade” in several experiments that also ruled out alternative explanations for the problem.

PROVIDENCE, R.I. [Brown University] — Recreational fishing is a major contributor to the rapid decline of important salt marshes along Cape Cod because it strips top predators such as striped bass, blue crabs, and smooth dogfish out of the ecosystem, according to new research by Brown University ecologists.

With far fewer predators in areas where recreational fishing is prevalent, native Sesarma crabs have had relatively free rein to eat salt marsh grasses, causing the ecosystem to collapse, said Mark Bertness, chair of Brown’s Department of Ecology and Evolutionary Biology and the paper’s senior author. He led a series of experiments and measurements published online in the journal Ecology that he said unavoidably implicate recreational fishing in marsh die-off. (more…)

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Not a One-Way Street: Evolution Shapes Environment of Connecticut Lakes

Environmental change is the selective force that preserves adaptive traits in organisms and is a primary driver of evolution. However, it is less well known that evolutionary change in organisms also trigger fundamental changes in the environment.

Yale University researchers found a prime example of this evolutionary feedback loop in a few lakes in Connecticut, where dams built 300 years ago in Colonial times trapped a fish called the alewife.

In a study published May 23 in the journal Proceedings of the Royal Academy B, the Yale team describes how this event fundamentally changed the structure of the alewife and, with it, the water flea that the alewife feeds upon and the food chain that supports them both. (more…)

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Escalating Arms Race: Predatory Sea Urchins Drive Evolution

ANN ARBOR, Mich.— Nature teems with examples of evolutionary arms races between predators and prey, with the predator species gradually evolving a new mode of attack for each defensive adaptation that arises in the prey species.

These adaptations are often portrayed as reciprocal, with prey and predator acting as two sides in an endless evolutionary tug of war known as co-evolution. (more…)

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Human’s Oldest Ancestor Found in Burgess Shale

*Pikaia is most primitive vertebrate known*

Researchers from the University of Toronto, the Royal Ontario Museum (ROM) and the University of Cambridge have confirmed that a 505 million-year-old creature, found only in the Burgess Shale fossil beds in Canada’s Yoho National Park, is the most primitive known vertebrate and therefore the ancestor of all descendant vertebrates, including humans.

The research team’s analysis proves the extinct Pikaia gracilens is the most primitive member of the chordate family, the group of animals that today includes fish, amphibians, birds, reptiles and mammals. Their study is based on the analysis of 114 specimens and is published in the British scientific journal Biological Reviews. (more…)

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Redder Ladybirds More Deadly, Say Scientists

A ladybird’s colour indicates how well-fed and how toxic it is, according to an international team of scientists.

Research led by the Universities of Exeter and Liverpool directly shows that differences between animals’ warning signals reveal how poisonous individuals are to predators.

Published in the journal Functional Ecology, the research shows that redder ladybirds are more poisonous than their paler peers. The study reveals that this variation is directly linked to diet in early life, with better-fed ladybirds being more visible and more deadly.

Ecologists have long assumed that there are no individual differences between the warning signals of animals of the same species. More recently, scientists have identified variation between individuals’ warning signals, but have not known if these differences were meaningful and linked to levels of toxicity. (more…)

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Sea Change – Penguins Provide Window into Shifting Antarctic Ecosystem

What’s the best way to study the Antarctic’s ecosystem? Follow the penguins.

Scientists are tracking penguins on land, under the sea, and even from space to unravel the environmental dynamics in the West Antarctic Peninsula as the region experiences climate change.

“We’re not just down there bird watching,” said Matthew Oliver, assistant professor of oceanography in UD’s College of Earth, Ocean, and Environment. “This is a concerted effort to put the whole ecosystem together.” (more…)

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