My picks from ScienceDaily

Sleep Quantity Affects Morning Testosterone Levels In Older Men

The testosterone levels of healthy men decline as they get older. As sleep quality and quantity typically decrease with age, objectively measured differences in the amount of sleep a healthy older man gets can affect his level of testosterone in the morning, according to a study published in the April 1st issue of the journal SLEEP.
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“The results of the study raise the possibility that older men who obtain less actual sleep during the night have lower blood testosterone levels in the morning,” said Penev. “Although the findings suggest that how long a person sleeps may be an indicator of age-related changes in important hormone signals in the body, future studies are needed to determine the importance of these relationships for the health of older adults.”

Are All Male’s Liars And Cheaters? Yes — If They’re Crayfish!:

Intimidation and threats are common throughout society, whether it’s in the school playground, sporting arena or boardroom. Threatening behaviour is equally widespread among non-human animals. Individuals signal their superior strength to competitors to obtain food, resolve territorial disputes and acquire mates. Current theory insists that signals of strength should be honest. Surprisingly researchers have found that dishonest signals are used routinely during dominance disputes by male Australian crayfish.

Making No Bones About It: Digestion In Burmese Pythons:

Burmese pythons don’t eat very often, but when they do they like to pig out, ingesting the whole of their prey. There’s very little waste as they are able to digest everything, apart from hair and feathers. Dr Jean-Hervé Lignot (Louis Pasteur University) and Dr Robert K. Pope (Indiana University South Bend) will talk about the implications this has on the way these snakes digest food on Saturday 31st March at the Society for Experimental Biology’s Annual Meeting in Glasgow.

Male Owls Pitch Their Hoots To Advertise Body Weight To Competitors:

Why do male owls hoot? Researchers from the Centre d’Études Biologiques de Chizé (France) and the University of Sussex (UK) have studied the vocal communication of male European Scops owls, one of the smallest living species of nocturnal raptors. The study, published in the April issue of the American Naturalist, was conducted between June 2003 and June 2005 on the isle of Oléron, off the west coast of France, where Christian Bavoux and Guy Burneleau have been studying the local scops owl population since 1981.

Spiteful Soldiers And Sex Ratio Conflict Among Parasitoid Wasps:

The social insects provide some of the most fascinating examples of altruism in the natural world, with sterile workers sacrificing their own reproduction for the greater good of the colony.

Flowers Shape Themselves To Guide Their Pollinators To The Pollen:

Why do flowers specialize on different pollinators? For example, both bats and hummingbirds pollinate plants in tropical forests; why adapt to just one instead of using both? Biologists often assume that tradeoffs contribute to such specialization (the jack of all pollinators is master of none), yet surprisingly little evidence exists in support of this idea.

Why Are There So Many More Species Of Insects? Because Insects Have Been Here Longer:

J. B. S. Haldane once famously quipped that “God is inordinately fond of beetles.” Results of a study by Mark A. McPeek of Dartmouth College and Jonathan M. Brown of Grinnell College suggest that this fondness was expressed not by making so many, but rather by allowing them to persist for so long. In a study appearing in the April issue of the American Naturalist, McPeek and Brown show that many insect groups like beetles and butterflies have fantastic numbers of species because these groups are so old. In contrast, less diverse groups, like mammals and birds, are evolutionarily younger.

Biologist And Physicist Team Up To Study Alligator’s ‘Death Roll’:

Other than on television, few of us have ever seen the spectacular spin (and ghastly consequences) of the crocodilian “death roll.” But, in a basement laboratory in the University’s Schmucker’s Science building, a biologist and physicist have been video taping young alligators spinning with the ferocity of their older, larger cousins in the wild.

To Sleep, Perchance To Dream: New Insight Into Melatonin Production:

In the April 1 issue of Genes & Development, a Korean research team led by Dr. Kyong-Tai Kim (Pohang University) describes how melatonin production is coordinated with the body’s natural sleep/wake cycles.
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Dr. Kim and colleagues uncovered the mechanism of rhythmic control of AANAT mRNA translation, and thereby melatonin synthesis. The researchers found that rodent AANAT mRNA translation is mediated by IRES (internal ribosome entry site) elements in the 5′ end of the transcript, through binding of another protein, called hnRNP Q. In fact, siRNA knock-down of hnRNP Q reduced AANAT and melatonin production under nocturnal conditions.