So, if you’ve been keeping up with the blog you’ve probably
read a few posts about my cognition apparatuses and seen plenty of photos.
Link here and
here. If you haven’t read them, I’ll summarize
briefly. I’m a graduate student on the Hyena Project and I’m testing the
cognitive abilities of hyenas with a general problem solving task. I’m
interested in the individual, social, and ecological factors that affect how
good they are at learning to solve novel problems.
Studying cognition in the wild poses unique challenges…
I’ve been out here for four months now- so what’s happening
with the hyenas? So far, I’ve mostly been conducting familiarization trials
with the hyenas to help the hyenas learn to associate food with the puzzle box.
In familiarization trials I leave the puzzle box wide open with food easily
accessible (no problem solving required to open). This is to overcome any
neophobia (fear of novelty or new things) a hyena might have and to increase
their motivation to participate in cognition trials. There is a lot of
increasing interest in testing the cognition of wild animals, since animals in
captivity grow up in an unnatural environment. However, in the wild the results
of a cognition study can be skewed based on which individuals decide to
participate in trials. I put out the puzzle box within eyesight of a hyena and
then the hyena decides whether or not to investigate the puzzle box or walk
away. This can definitely skew results if hyenas with specific characteristics
are more likely than others to participate. But, studying wild hyenas gives me
the chance to assess how urbanization might affect learning in the wild.
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A hyena watches a herd of cattle (credit hyaenidae.org). |
How does urbanization affect animal cognition?
I’m collecting data in two different parts of the Maasai
Mara National Reserve: Serena and Talek. In Talek, hyenas live on the border of
the reserve and regularly encounter Maasai villagers, heavy and poorly
regulated tourism, cattle grazing, and snares from poachers. In other words,
they experience a high degree of “urbanization”. In Serena, hyenas are well
protected from poaching and cattle grazing and tourism is strictly regulated.
There’s a lot of interest in the scientific community on how the dramatically
changed urbanized environments affects animals, and in particular, animal
cognition. A large body of research suggests that rapidly changing environments,
like urbanized ones, select for bigger brains and greater smarts
(Marino 2005). Some studies have shown that
urban animals have larger brains than rural animals
(Maklakov et al. 2011; Snell-Rood & Wick 2013) and that large brained
animals are better at invading new habitats
(Amiel et al. 2011; Sol et al. 2008; Sol et al. 2005). However, in the short run
changing environments can be highly stressful for animals and many species are
unable to cope with change, resulting in extinction. In addition, large brained
animals are also more like to be endangered
(Abelson 2016).
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Some hyenas investigate the box, but even more of them hang out at a distance without ever touching it. |
Talek hyenas are more neophobic?
So far, it looks like Talek hyenas might be more neophobic
than Serena hyenas because they’re less likely to eat the bait from inside the
box. I’ve collected 149 trials with 63 different hyenas in Talek and 176 trials
with 69 different hyenas in Serena. Out
of these trials in just 28% trials a hyena fed from the puzzle box in Talek
while in 38% of trials in Serena a hyena fed from the puzzle box. These
were all familiarization trials (no problem solving required) where the box was
left wide open with the food easily accessible. All the hyena has to do is walk
up to the box, stick their head inside and eat the food. Whether or not a hyena is willing to eat food from a novel source could indicate their level of neophobia (though it could also indicate their food motivation level). Since a greater percentage of Serena hyenas were willing to feed from the
puzzle box this could suggest that hyenas in Talek are more neophobic (more
nervous about the puzzle box). However, it’s important to note that these are
raw percentages and I have not controlled for the fact that some hyenas have gotten more than one trial with the box.
Neophobia and urbanization
Other studies have also found that urban animals are more
neophobic than rural animals in addition to being better problem solvers
(Griffin et al. 2015; Miranda et al. 2013; Audet et
al. 2016).
However, other studies show that animals
in novel or urban environments are less neophobic
(Martin & Fitzgerald 2005; Møller 2009). While neophobia may help individuals
to avoid dangers in a novel environment, it may also make them less likely to
find novel sources of food to exploit.
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VENI, an immigrant male hyena in Serena was fairly nervous about approaching the box. |
Neophobia and problem solving
The relationship between neophobia and problem solving in
animals is mostly inconclusive
(Griffin & Guez 2014) but previous research with
hyenas by hyena lab alumni Sarah Benson-Amram suggests that neophobic hyenas are
less likely to successfully problem solve
(Benson-Amram et al. 2013; Benson-Amram & Holekamp
2012).
If Talek hyenas really are more
neophobic then they might be less likely to solve my puzzle box - if neophobia
is a causal factor in performance and not just correlative. My hypothesis is
that Talek hyenas will be better problem solvers, but neophobia could
superficially make them worse. I.e. Talek hyenas
could be better problem
solvers than Serena hyenas in reality, but neophobia could prevent them from
interacting with the box making them look worse on paper. Therefore, I have to
make sure to get as many familiarization trials to both Talek and Serena hyenas
as possible to try and overcome any effect of neophobia so that I can test the
effect of urbanization independently. Hopefully Talek and Serena hyenas will
start getting test trials soon where they have to learn how to open the box to retrieve
the bait inside. Who knows what I’ll find out!
References cited
Abelson, E.S., 2016. Brain size is correlated with
endangerment status in mammals. Proceedings. Biological sciences / The Royal
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Amiel, J.J., Tingley,
R. & Shine, R., 2011. Smart moves: effects of relative brain size on
establishment success of invasive amphibians and reptiles. PloS one,
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Audet, J.-N., Ducatez,
S. & Lefebvre, L., 2016. The town bird and the country bird: problem
solving and immunocompetence vary with urbanization. Behavioral Ecology,
27(2), pp.637–644.
Benson-Amram, S. &
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Biological sciences / The Royal Society, 279(1744), pp.4087–95.
Benson-Amram, S.,
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crocuta. Animal Behaviour, 85(2), pp.349–356.
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Griffin, A.S.,
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environments. Biology letters, 7(5), pp.730–2.
Marino, L., 2005. Big
brains do matter in new environments. Proceedings of the National Academy of
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Martin, L.B. &
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