-monkeys-cosy-alliance-with-wolves-looks-like-
domestication.html#.VXKGOrxxvdQ.email
Monkeys' cosy alliance with
wolves looks like domestication
- 17:33 05 June 2015 by Bob Holmes
- For similar stories, visit the Evolution Topic Guide
In the alpine grasslands of eastern Africa, Ethiopian wolves and
gelada monkey are giving peace a chance. The geladas – a type
of a baboon – tolerate wolves wandering right through the middle
of their troops, while the wolves ignore potential meals of baby
geladas in favour of rodents, which they can catch more easily
when the monkeys are present.
gelada monkey are giving peace a chance. The geladas – a type
of a baboon – tolerate wolves wandering right through the middle
of their troops, while the wolves ignore potential meals of baby
geladas in favour of rodents, which they can catch more easily
when the monkeys are present.
The unusual pact echoes the way dogs began to be domesticated
by humans (see box, below), and was spotted by primatologist
Vivek Venkataraman, at Dartmouth College in New Hampshire,
during field work at Guassa plateau in the highlands of north-central
Ethiopia.
by humans (see box, below), and was spotted by primatologist
Vivek Venkataraman, at Dartmouth College in New Hampshire,
during field work at Guassa plateau in the highlands of north-central
Ethiopia.
Even though the wolves occasionally prey on young sheep and goats
, which are as big as young geladas, they do not normally attack the
monkeys – and the geladas seem to know that, because they do
not run away from the wolves.
, which are as big as young geladas, they do not normally attack the
monkeys – and the geladas seem to know that, because they do
not run away from the wolves.
"You can have a wolf and a gelada within a metre or two of each
other and virtually ignoring each other for up to 2 hours at a time,
" says Venkataraman. In contrast, the geladas flee immediately to
cliffs for safety when they spot feral dogs, which approach
aggressively and often prey on them.
other and virtually ignoring each other for up to 2 hours at a time,
" says Venkataraman. In contrast, the geladas flee immediately to
cliffs for safety when they spot feral dogs, which approach
aggressively and often prey on them.
When walking through a troop, the wolves seem to take care to
behave in a non-threatening way. They move slowly and calmly
as they forage for rodents and avoid the zigzag running they use
elsewhere, Venkataraman observed.
behave in a non-threatening way. They move slowly and calmly
as they forage for rodents and avoid the zigzag running they use
elsewhere, Venkataraman observed.
Deliberate association
This suggested that they were deliberately associating with the
geladas. Since the wolves usually entered gelada groups during
the middle of the day, when rodents are most active, he wondered
whether the geladas made it easier for the wolves to catch the
rodents – their primary prey.
geladas. Since the wolves usually entered gelada groups during
the middle of the day, when rodents are most active, he wondered
whether the geladas made it easier for the wolves to catch the
rodents – their primary prey.
Venkataraman and his colleagues followed individual wolves for
17 days, recording each attempted capture of a rodent, and
whether it worked. The wolves succeeded in 67 per cent of
attempts when within a gelada troop, but only 25 per cent of the
time when on their own.
17 days, recording each attempted capture of a rodent, and
whether it worked. The wolves succeeded in 67 per cent of
attempts when within a gelada troop, but only 25 per cent of the
time when on their own.
It's not yet clear what makes the wolves more successful when
they hunt within gelada groups. It could be that the grazing
monkeys flush out the rodents from their burrows or vegetation,
Venkataraman suggests.
they hunt within gelada groups. It could be that the grazing
monkeys flush out the rodents from their burrows or vegetation,
Venkataraman suggests.
Mobile hide
Another possibility is that the monkeys, which are about the
same size and colour as the wolves, distract the rodents and
make it easier for the wolves to approach undetected. "I like
to think of it as a mobile hide," says Claudio Sillero, a
conservation biologist at the University of Oxford who studies
the critically endangered Ethiopian wolves. "The wolves benefit
from hiding in the herd."
same size and colour as the wolves, distract the rodents and
make it easier for the wolves to approach undetected. "I like
to think of it as a mobile hide," says Claudio Sillero, a
conservation biologist at the University of Oxford who studies
the critically endangered Ethiopian wolves. "The wolves benefit
from hiding in the herd."
Whatever the mechanism, the boost to the wolves' foraging
appears to be significant enough that the wolves almost never
give in to the temptation to grab a quick gelada snack. Only
once has Venkataraman seen a wolf seize a young gelada,
and other monkeys quickly attacked it and forced it to drop
the infant, then drove the offending wolf away and prevented
it from returning later.
appears to be significant enough that the wolves almost never
give in to the temptation to grab a quick gelada snack. Only
once has Venkataraman seen a wolf seize a young gelada,
and other monkeys quickly attacked it and forced it to drop
the infant, then drove the offending wolf away and prevented
it from returning later.
The wolves may benefit from associating with other species
as well. For example, Sillero has noted that they also tend
to forage in the vicinity of herds of cattle, which may help
them catch rodents. Other predators might also be doing
this without anyone noticing, says Colin Chapman, a
primatologist at McGill University in Montreal, Canada. "I
don't think we've looked at it very much, because the
predators are usually scared off by people. I think it could
be pretty common," he says.
as well. For example, Sillero has noted that they also tend
to forage in the vicinity of herds of cattle, which may help
them catch rodents. Other predators might also be doing
this without anyone noticing, says Colin Chapman, a
primatologist at McGill University in Montreal, Canada. "I
don't think we've looked at it very much, because the
predators are usually scared off by people. I think it could
be pretty common," he says.
Posts
No comments:
Post a Comment