Tag Archives: reproduction

Fructose More Toxic than Table Sugar in Mice

Sensitive Toxicity Test Used Sugars in Doses Like What We Eat

When University of Utah biologists fed mice sugar in doses proportional to what many people eat, the fructose-glucose mixture found in high-fructose corn syrup was more toxic than sucrose or table sugar, reducing both the reproduction and lifespan of female rodents. (more…)

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Nourishing people—and an economy

Milk has a reputation for strengthening bones. In Malawi, the growing dairy industry is strengthening the livelihoods of small dairy farmers and the health of the country’s inhabitants.

In an effort to double the capacity of Malawi’s dairy value chain, MSU researchers led by Puliyur MohanKumar, professor in the College of Veterinary Medicine, are applying successful outcomes from a similar MSU partnership project that helped transform India’s dairy industry. India, now the world’s top milk producer, shares similar environmental and cultural traits with Malawi. (more…)

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March of the Pathogens: Parasite Metabolism Can Foretell Disease Ranges under Climate Change

Knowing the temperatures that viruses, bacteria, worms and all other parasites need to grow and survive could help determine the future range of infectious diseases under climate change, according to new research.

Princeton University researchers developed a model that can identify the prospects for nearly any disease-causing parasite as the Earth grows warmer, even if little is known about the organism. Their method calculates how the projected temperature change for an area would alter the creature’s metabolism and life cycle, the researchers report in the journal Ecology Letters. (more…)

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Yellowstone Wolf Study Reveals How to Raise Successful Offspring

What are the key ingredients to raising successful, self-sufficient offspring? A new life sciences study using 14 years of data on gray wolves in Yellowstone National Park indicates that cooperative group behavior and a mother’s weight are crucial.

“A female’s body weight is key in the survival of her offspring, and cooperation in the protection and feeding of young pups pays off in terms of the production of offspring,” said Robert Wayne, a professor of ecology and evolutionary biology at UCLA and co-author of the new research, published this week in the online edition of the Journal of Animal Ecology. (more…)

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Jekyll and Hyde Bacteria Aids or Kills, Depending on Chance

EAST LANSING, Mich. — Living in the guts of worms are seemingly innocuous bacteria that contribute to their survival. With a flip of a switch, however, these same bacteria transform from harmless microbes into deadly insecticides.

In the current issue of Science, Michigan State University researchers led a study that revealed how a bacteria flips a DNA switch to go from an upstanding community member in the gut microbiome to deadly killer in insect blood.

Todd Ciche, assistant professor of microbiology and molecular genetics, has seen variants like this emerge sometimes by chance resulting in drastically different properties, such as being lethal to the host or existing in a state of mutual harmony. Even though human guts are more complex and these interactions are harder to detect, the revelation certainly offers new insight that could lead to medical breakthroughs, he said. (more…)

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Pollination with Precision: How Flowers Do It

Pollination could be a chaotic disaster. With hundreds of pollen grains growing long tubes to ovules to deliver their sperm to female gametes, how can a flower ensure that exactly two fertile sperm reach every ovule? In a new study, Brown University biologists report the discovery of how plants optimize the distribution of pollen for successful reproduction.

PROVIDENCE, R.I. [Brown University] — Next Mother’s Day, say it with an evolved model of logistical efficiency — a flower. A new discovery about how nature’s icons of romance manage the distribution of sperm among female gametes with industrial precision helps explain why the delicate beauties have reproduced prolifically enough to dominate the earth.

In pollination, hundreds of sperm-carrying pollen grains stick to the stigma suspended in the middle of a flower and quickly grow a tube down a long shaft called a style toward clusters of ovules, which hold two female sex cells. This could be a chaotic frenzy, but for the plant to succeed, exactly two fertile sperm should reach the two cells in each ovule — no more, no less. No ovule should be left out, either because too many tubes have gone elsewhere, or because the delivered sperm don’t work. (more…)

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Pregnant Primates Miscarry When New Male Enters Group

ANN ARBOR, Mich.— Pregnant female geladas show an unusually high rate of miscarriage the day after the dominant male in their group is replaced by a new male, a new University of Michigan study indicates.

The “Bruce effect” – in which pregnant females spontaneously miscarry after being exposed to an unfamiliar male – has been found repeatedly in laboratory rodents. However, no conclusive evidence for this effect had ever been demonstrated in a wild population prior to this study. Geladas are Old World monkeys that are close relatives of baboons. (more…)

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Mother of All Mergers

*Yeast open a window on a spectacular step in evolution*

Around 800 million years ago, some of the one-celled organisms that constituted the whole of earthly life took an evolutionary leap that changed everything.

They started to band together, eventually evolving into complex organisms like animals and plants.

How that leap happened is a mystery that has eluded scientists. But now University of Minnesota researchers have coaxed normally solitary baker’s yeast cells into reenacting the leap, giving science a way to study not only this watershed event but its implications. (more…)

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