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  • Sinister Cannibals or Nurturing Fathers?

    Sinister Cannibals or Nurturing Fathers?

    In majority of sexually reproducing species females are the choosy ones. Generally, females invest more in offspring during pregnancy and post-natal care. Males try many tricks (fighting with other males, making elaborate dances, providing nuptial gifts, carrying showy and difficult to maintain body ornaments etc.) to prevent being filtered out in female preferences. Parental investment is a determinant in choosiness. In this post we will take a look at a spectrum of male behavior in parental care. Pipefishes and mudskippers […]

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  • After Death: Fossil Carrion Beetles

    After Death: Fossil Carrion Beetles

    Until very recently the oldest known carrion beetle fossils were 50 million years old. The fossil discoveries coming from Daohugou and Jehol rock deposits in Northeastern China extended our knowledge further back till 160 million years ago. During Jurassic period dinosaur abundance had a cascading influence on animal world. When a dinosaur died its carcass became a protein rich multi-generational feeding island. Insects including carrion beetles most certainly exploited this opportunity. Therefore carrion beetle evolution took a new turn leading […]

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  • What is A Species? Christina Choate (2011)

    What is A Species? Christina Choate (2011)

    How did diversity of life on our planet form? How does it maintain itself? Species concept is most certainly a very convenient construct for biologists who are trying to understand life. Rightly so, Charles R. Darwin titled his masterpiece as On the Origin of Species for the concept was crucial in developing a theory that is central to biology. The species argument is quite parallel to that of transitional fossils. Both terms are plastic and represent data points along a […]

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  • When and Why We Lost Hair?

    When and Why We Lost Hair?

    When and why our ancestors began to wear clothing is a curious story. Clothing may have emerged for insulation of body heat. Similarly it also have provided a means to carry things and improve mobility. Cold snaps engulfed the earth many times. Using ice cores from Antarctica scientists identified 8 glacial cycles within the last 800 thousand years alone. An archaelogical site from Israel provides the earliest evidence of controlled fire by humans spanning the same time period. We know […]

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  • The Botany of Desire – Michael Pollan – PBS (2009)

    The Botany of Desire – Michael Pollan – PBS (2009)

    Domestication is a defining feature of recent human evolution. In animals first trait selected by humans was behavior. In plants harvestability through selection of non-shattering seeds was the first trait of domestication. Plant domestication paved the way to agriculture which enabled highly specialized sedentary human societies. Domesticated plants differ from their wild ancestors in distinct ways that can be categorized under a term called as the domestication syndrome. Domestication syndrome includes reduced shattering of seeds (seeds don’t separate from the […]

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  • The Passionate Wait

    The Passionate Wait

    In the second part of the passion flower series events before the opening of the flowers are outlined. Drought conditions in summer of 2011 made extrafloral nectaries of the plant a very busy place. The water budget of the plants is strongest early in the morning. Flowers do not open until the middle of the day. At first, passion flower is generous to the ants in the morning providing ample volume of nectar. On the other hand, pollinators remain hungry. […]

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  • Ants – Nature’s Secret Power (2006)

    Ants – Nature’s Secret Power (2006)

    Ants, bees and wasps make up only 3 percent of animal diversity yet they may constitute up to 50 percent of the total animal biomass in land habitats. Bert Hölldobler is a leading entomologist (scientist who studies insects). He collaborated with ant biologist E.O. Wilson and developed the field of Sociobiology. The documentary does an excellent job introducing us observations coming from both natural and laboratory setting. First observation comes from the European red wood ants (Formica polyctena). These ants […]

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  • Daytime Hunting of Barred Owl (Strix varia)

    Daytime Hunting of Barred Owl (Strix varia)

    On April 16th 2011, a barred owl glided over my head while I was filming something else along the Orange Trail of the State Botanical Garden of Georgia in Athens, GA. Hunting during daytime indicates that this individual has extra mouths to feed. You can hear the altruistic alarm calls of other nervous birds and rodents. The high pitched alarm call (of a chipmunk?) is particularly audible immediately before each move of the owl. I deliberately kept the scenes long […]

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  • Acid Attack

    Acid Attack

    Wildflowers can build a community of allies for defence. Ants defend extrafloral nectaries (nectar produced in organs other than flowers) of a passion flower vine against herbivores. This is an example of plant-animal interaction evolved to solve at least three biological problems. [1] Extrafloral nectaries seen in this video resemble butterfly eggs.  Butterflies avoid laying their eggs on host plants if they see other eggs. This is particularly true for two species of butterflies Gulf fritillary (Agraulis vanillae) and Variegated […]

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