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My picks from ScienceDaily

Ewwwww! UCLA Anthropologist Studies Evolution’s Disgusting Side:

Behind every wave of disgust that comes your way may be a biological imperative much greater than the urge to lose your lunch, according to a growing body of research by a UCLA anthropologist.

The Delayed Rise Of Present-day Mammals:

It took 10 to 15 million years after the dinosaurs were wiped out before modern mammals – including our ancient human ancestors – were able to diversify and rise to their present-day prominence across the globe, a landmark new study has found. The surprise finding overturns the widely held belief that the ancestors of modern mammals were able to quickly evolve and spread to fill many of the empty niches left behind following the mass extinctions of dinosaurs and many other large animals when a huge asteroid crashed into the Earth about 65 million years ago.

A High Beef Diet During Pregnancy Linked To Lower Sperm Counts In Sons:

A mother’s high beef consumption while pregnant was associated with lower sperm counts in her son, according to a study led by researchers at the University of Rochester.

Transplanting Organs From Animals To Humans: What Are The Barriers?:

Given the huge shortage of donor organs, researchers have been trying to find ways to transplant animal organs across different species (known as “xenotransplantation”), with the eventual aim of transplanting animal organs into humans. The major stumbling block, says Dr Muhammad Mohiuddin (US National Heart, Lung, and Blood Institute) in a paper in PLoS Medicine, is that the immune system in the animal receiving the organ tends to reject the transplant.

Comments

  1. #1 Alan Kellogg
    March 30, 2007

    On Post Cretaceous Mammalian Diversification

    What took them so long? The pattern they noted was seen previously after the Permian Extinction. You’d think it would take time for conditions to settle down, and that’s what we see in the Cretaceous Extinction Event. Once conditions changed to something more stable, then species better able to take advantage of such gained over earlier forms.

    Then too there is the matter of pre-K/T boundary mammalian diversification. As I understand it, the great majority of eutherian orders arose during the Jurassic or Cretaceous. Wih only the rodents appearing during the Tertiary.

    Note too that the article apparently focuses on placental mammals, quite ignoring monotremes, marsupials, and multituberculates (assuming the multis were even true mammals to begin with, or mammaloids descended from a different mammallike reptile line).

    All in all Post Cretaceous events pretty much match Post Permian events in general outline. After all, both dinosaurs and mammals didn’t appear until sometime after the Permian Extinction.

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