House finches avoid sick members of their own
species, scientists said Wednesday in a finding that could be useful for
tracking the spread of diseases like bird flu that also affects humans.
House finches avoid sick members of their own
species, scientists said Wednesday in a finding that could be useful for
tracking the spread of diseases like bird flu that also affects humans.
Laboratory tests showed that the house finch, a
particularly social North American species, was able to tell the difference
between sick and healthy fellow birds and tended to avoid those that were
unwell.
This was the first time that avoidance of sick
individuals, already observed in lobsters and bullfrog tadpoles, has been shown
in birds, according to a paper published in the Royal Society journal Biology
Letters.
"In addition, we found variation in the
immune response of house finches, which means that they vary in their ability
to fight off infections," co-author Maxine Zylberberg of the California
Academy of Sciences told AFP.
"As it turns out, individuals who have
weaker immune responses and therefore are less able to fight off infections,
are the ones who most avoid interacting with sick individuals."
This all meant that there were differences
between individual birds' susceptibility to disease, the time it would take
them to recuperate and their likeliness to pass on the disease.
"These are key factors that help to
determine if and when an infectious disease will spread through a group of
birds," said Zylberg -- and how quickly.
