If you do the activity, send me an email to let me know:
ana.gil@educa.madrid.org
Germs
explain some animal behaviors
The way hyenas smell is no laughing matter. Kevin Theis has been known to
empty a laboratory of fellow scientists just by opening a bottle of what he
calls “hyena butter.”
Hyenas secrete the pasty substance from a pouch tucked under their tails. This
so-called butter is seriously stinky. It’s also crucial to how these African
mammals communicate, explains Theis. An ecologist, he studies animal behavior
and microbiology at Michigan State University in East Lansing. (Behavior is how
an animal reacts to a particular situation or stimulus.)
Hyenas rub their pungent paste onto grass stalks — a practice called scent
marking. The smell of that musky paste is something only another hyena could
love. In fact, hyenas eagerly sniff the secretions to identify one another.
Scents are one of the many ways animals are known to trade information. Indeed,
odors can share a host of important data. What scientists are just beginning to
realize is that when hyenas use scents to communicate, it’s bacteria that do
most of the “talking.”
Kevin Theis takes blood an Each spotted hyena has a different ratio of
dozens of different bacteria in its scent pouch. That means each paste has a
different recipe — and odor.
Our noses aren't sensitive enough to pick up their subtle differences. Still,
Theis can sort them out by identifying the bacteria responsible. He does this
by analyzing the recipe of each bacterium's DNA. Its building blocks appear in
a very precise order — or sequence. It is so precise and unique to the
bacterium that this genetic sequence is a bit like a fingerprint.
Each spotted hyena seems to have its own mix of bacteria — and unique scent. A
deep sniff of a pasted grass stalk can tell another hyena who marked it. And if
it was a female, her scent also will signal whether she is pregnant or is
nursing a cub.
Theis found that bacteria living in the scent pouch of hyenas produce the
chemicals that give the animals their particular smell. Here’s why: Inside a
hyena's scent pouch, bacteria feed on nutrients. These probably include fats
and proteins derived from what the animal ate. Just like people, those microbes
don't use everything they eat. Whatever doesn’t fuel a bacterium’s growth or
reproduction will be expelled as waste. Some of those wastes are fatty
materials that easily evaporate. They also make the paste stinky.
Germs explain some animal behaviors
Hyenas secrete the pasty substance from a pouch tucked under their tails. This so-called butter is seriously stinky. It’s also crucial to how these African mammals communicate, explains Theis. An ecologist, he studies animal behavior and microbiology at Michigan State University in East Lansing. (Behavior is how an animal reacts to a particular situation or stimulus.)
Hyenas rub their pungent paste onto grass stalks — a practice called scent marking. The smell of that musky paste is something only another hyena could love. In fact, hyenas eagerly sniff the secretions to identify one another. Scents are one of the many ways animals are known to trade information. Indeed, odors can share a host of important data. What scientists are just beginning to realize is that when hyenas use scents to communicate, it’s bacteria that do most of the “talking.”
Our noses aren't sensitive enough to pick up their subtle differences. Still, Theis can sort them out by identifying the bacteria responsible. He does this by analyzing the recipe of each bacterium's DNA. Its building blocks appear in a very precise order — or sequence. It is so precise and unique to the bacterium that this genetic sequence is a bit like a fingerprint.
Each spotted hyena seems to have its own mix of bacteria — and unique scent. A deep sniff of a pasted grass stalk can tell another hyena who marked it. And if it was a female, her scent also will signal whether she is pregnant or is nursing a cub.
Theis has watched hyenas sniff the paste left by others. The animals then
behave in one way or another, depending on what they learned.
"Females spent much more time sniffing pastes from other females," he
says. This would “suggest that the scent of an alien female is very important.”
And that makes sense, since females rule hyena clans. In contrast, the whiff of
some alien male might not matter to her so much.d other samples from a hyena
that has been temporarily drugged to sleep. Theis wants to know how hyenas rely
on bacteria to make the distinctive scents that these animals use to identify
one another.
Hyenas rely
on these unique scents to identify one another by species, sex and clan. That
is important information. “A critical part of most animals' behavior is an
effective communication system,” Theis observes.
Each spotted hyena has a different ratio of dozens of different bacteria in
its scent pouch. That means each paste has a different recipe — and odor.
Bacteria as “caller ID”
Animals are chock full of bacteria. In each of us, there are an estimated
10 single-celled microbes for every one of our own human cells. We’re
outnumbered. But that's a good thing.
People and other animals share a symbiotic relationship with many bacteria. We
have evolved to help each other. We give bacteria a place to live and food to
eat. In turn, the bacteria work hard on our behalf. Bacteria on our skin, for
example, form a protective coating. It fights off the germs that can make us
sick. Bacteria in the gut help digest food, releasing the energy and nutrients
we need. These good bacteria also crowd out many bad bugs that can trigger
disease.
Those things have been studied for decades. Far newer: the role microbes play
in behavior.
Theis and his colleagues
reported their findings Dec. 3, 2013, in the Proceedings of the National
Academy of Sciences.
Science
News fos students
"Females spent much more time sniffing pastes from other females," he says. This would “suggest that the scent of an alien female is very important.” And that makes sense, since females rule hyena clans. In contrast, the whiff of some alien male might not matter to her so much.d other samples from a hyena that has been temporarily drugged to sleep. Theis wants to know how hyenas rely on bacteria to make the distinctive scents that these animals use to identify one another.
People and other animals share a symbiotic relationship with many bacteria. We have evolved to help each other. We give bacteria a place to live and food to eat. In turn, the bacteria work hard on our behalf. Bacteria on our skin, for example, form a protective coating. It fights off the germs that can make us sick. Bacteria in the gut help digest food, releasing the energy and nutrients we need. These good bacteria also crowd out many bad bugs that can trigger disease.
Those things have been studied for decades. Far newer: the role microbes play in behavior.
Science News fos students
- Vocabulary: to tuck; to rub; pungent; musky; odor; chock.
- What is hyena-butter?
- What is scent marking?
- What produce the chemicals responsible for the smell of hyena butter?
- Why does each hyena have a different scent?
- What do hyenas use their “butter” for?
- How many bacteria do we (humans) have in our bodies?
- Why do we have a symbiotic relationship with bacteria?
- How do bacteria help us?
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.