Giraffes May Be as Socially Complex as Chimps and Elephants
A
review of earlier research shows giraffes have the markings of social
creatures, including friendships, day care and grandmothers.
A researcher who studied in Kenya said that giraffes looked “like teenagers hanging out.”Credit...Zoe Muller
By Cara Giaimo
Giraffes
seem above it all. They float over the savanna like two-story ascetics,
peering down at the fray from behind those long lashes. For decades,
many biologists thought giraffes extended this treatment to their peers
as well, with one popular wildlife guide calling them “aloof” and capable of only “the most casual” associations.
But
more recently, as experts have paid closer attention to these lanky
icons, a different social picture has begun to emerge. Female giraffes
are now known to enjoy yearslong bonds. They have lunch buddies, stand guard over dead calves and stay close with their mothers and grandmothers. Females even form shared day care-like arrangements, called crèches, in which they take turns babysitting and feeding each others’ young.
Observations
like these have reached a critical mass, said Zoe Muller, a wildlife
biologist who completed her Ph.D. at the University of Bristol in
England.She and Stephen
Harris, also at Bristol, recently reviewed hundreds of giraffe studies
to look for broader patterns. Their analysis, published on Tuesday
in the journal Mammalia, suggests that giraffes are not loners, but
socially complex creatures, akin to elephants or chimpanzees. They’re
just a little more subtle about it.
Dr.
Muller’s sense of giraffes as secret socialites began in 2005, when she
was researching her master’s thesis in Laikipia, Kenya. There to
collect data on antelopes, she found herself drawn to the ganglier
ungulates. “They are so weird to look at,” she said. “If somebody
described them to you, you wouldn’t believe they even really existed.”
After
noticing that the same giraffes tended to spend time together — they
looked “like teenagers hanging out,” she said — Dr. Muller started to
read up on their lifestyles. “I was really surprised to see that all the
scientific books said that they were completely non-sociable,” she
said. “I thought, ‘Well, hang on. That’s not what I see at all.’”
In
an ecosystem full of trumpeting elephant matriarchs and fast-paced
cooperative lion hunts, it makes sense that the complexities of giraffe
sociality have been harder to spot, said Kim VanderWaal, an associate
professor at the University of Minnesota who has also studied them.
Giraffes don’t communicate in ways that are obvious to us,
and live quiet social lives low on visibly pally behaviors like
grooming or cooperative territorial defense. The use of digital cameras,
which help with tracking individuals by spot pattern, and social
network analysis, which can reveal hidden associative patterns, have
made it easier to tease out their relationships.
Giraffe
society seems to be built around strong pair bonds, especially between
mothers and their young, which coalesce into kinship groups, Dr. Muller
said. Watching females stay close to the body of a deceased calf
for many days, forgoing food and water, drove home for Dr. Muller “how
strong the attachments could be within a group,” she said.
But it’s been difficult to budge their detached reputation, she said.
For
this latest paper, she and Dr. Harris reviewed over 400 studies,
pulling together all of the evidence. The result is “a solid scholarly
review,” and supports the idea that “giraffe societies are way, way more
complex than most biologists think,” said Fred Bercovitch, a
conservation scientist at the Anne Innis Dagg Foundation, who was not
involved with the study.
It
also lays out a number of avenues for further research. While reading
through the studies, Dr. Muller noticed that giraffe females tend to
live long past their childbearing years. In other socially complex
animals, including humans and killer whales, post-reproductive individuals help younger generations thrive by providing wisdom and care.
This phenomenon, called the grandmother hypothesis,
should be tested in giraffes, Dr. Muller said. If it’s true, this would
have conservation implications, as older giraffes are often culled or trophy hunted. It would also provide more evidence that giraffesexperience
sophisticated forms of fellowship. The existence of those calf-care
crèches might even qualify giraffes as cooperative breeders, like
beavers or scrub jays, Dr. Muller said.
Others
are more cautious. “Giraffe social structure is complex,” and
researchers are just beginning to understand it, said Dr. VanderWaal,
who was also not involved in the study. “I think more research is needed
before we conclude that giraffes live in cooperative societies.”
But
all agree that we should continue craning our necks until we have a
better view. Giraffes are “one of the most recognizable animals in the
world,” Dr. Muller said. “And we’re only just starting to scratch the
surface.”
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