2015 Photo Contest, Nature, 1st prize



Anand Varma

National Geographic

13 June, 2013

Bird droppings gathered by the arboreal ant (Cephalotes atratus) to feed its larvae, sometimes contain a hidden menace: a parasitic nematode, Myrmeconema neotropicum. Once inside the ant, the nematode turns its host’s abdomen maroon, so that it mimics a ripe berry attractive to birds. To make its unwitting host even more enticing, the nematode induces the ant to walk with its abdomen raised.

Many parasites not only feed off their hosts, but appear to manipulate the host’s behavior in a way that is advantageous to the parasite’s life cycle. Recent research indicates that this influence occurs at a genetic level—certain parasite genes seem to be able to take control of the host’s brain. Research has shown that in some cases a single parasite gene is responsible for altering the host’s behavior, though in most instances it is thought that the phenomenon is brought about by a combination of genes.

About the photographer

Anand Varma

Anand Varma is a freelance photographer and videographer who grew up in Atlanta, Georgia. He started photographing natural history subjects while studying biology at the Universi...

Technical information

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Canon EOS 5D Mark III

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