Speaker 1: Welcome to brain Stuff, a production of iHeartRadio, Hey brain
Speaker 1: Stuff Lauren Vogelbaum here Curious, Lively and social. Common Marmosets
Speaker 1: are a group of monkeys found primarily in the forested
Speaker 1: areas of central Brazil and neighboring areas of South America.
Speaker 1: There are more than twenty subspecies of marmosets, including the
Speaker 1: pygmy marmoset, which is the world's smallest monkey. It weighs
Speaker 1: on average just over four ounces that's about one hundred
Speaker 1: and twenty grams and measures just over five inches in
Speaker 1: length or about twelve centimeters. Marmosets are members of one
Speaker 1: of five families of primates called Plattarines or New World monkeys.
Speaker 1: That's because at some point millions of years ago they
Speaker 1: separated from the primates of Africa and wound up on
Speaker 1: the other side of the Atlantic. The apes and so
Speaker 1: called Old World monkeys are catarines. Marsets are almost exclusively
Speaker 1: tree dwellers. Their nostrils are rounded and further apart than catarines,
Speaker 1: and though they do use their tails for balance, their
Speaker 1: tails are not prehensile, meaning they can't grasp things with them.
Speaker 1: Those tails are banded and long, usually longer than their bodies.
Speaker 1: Even non pygmy types are pretty small. The average male
Speaker 1: marmoset weighs about nine ounces or two hundred and fifty grams,
Speaker 1: and will be just over seven inches in length that's
Speaker 1: about eighteen centimeters. Females are just a little smaller. Their
Speaker 1: facial skin is pale, but it darkens in the sun.
Speaker 1: They're covered with fur that's flecked with brown, gray, and yellow.
Speaker 1: They have large white ear tufts and the white blaze
Speaker 1: on their forehead. Their hands and feet look very similar
Speaker 1: to squirrels. Their thumbs are not opposable, and they have
Speaker 1: claw like nails on all but their big toe. They
Speaker 1: use these claws to help them move through the trees quickly,
Speaker 1: using all four legs like squirrels, but also to scrap
Speaker 1: and scratch tree bark to get at the gums, app
Speaker 1: and resin that can make up to seventy percent of
Speaker 1: their diet. Marmosets also forage four insects and eat fruit, seeds, fungi, nectar,
Speaker 1: and small animals from snails to lizards to nestlings. They're
Speaker 1: active for eleven to twelve hours a day after feeding
Speaker 1: for an hour or so after waking, marmosets typically alternate
Speaker 1: between resting, feeding, and socializing with their family group. According
Speaker 1: to researchers, fifty three percent of their time is spent stationary,
Speaker 1: sprawled out like their on summer vacation, but it's not
Speaker 1: all rolling around the treetops. Being on the small side
Speaker 1: means marmosets are particularly vulnerable to predators, especially raptors and owls,
Speaker 1: tree snakes, wildcats, and mustelids like weasels, badgers, and ferrets.
Speaker 1: In the wild. The average life span of the Carmen
Speaker 1: marmoset is twelve years. For the article, this episode is
Speaker 1: based on to Works checked in with the Wisconsin National
Speaker 1: Primate Research Center at the University of Wisconsin Madison. The
Speaker 1: center is currently home to about two hundred and seventy
Speaker 1: marmosets who are helping researchers learn more about everything from
Speaker 1: parenting to Parkinson's disease. Specifically, Hastiff Works spoke by email
Speaker 1: with doctor Marina Emborg, a medical doctor, a professor of
Speaker 1: medical physics, and the director of the pre clinical Parkinson's
Speaker 1: Research program at the center. She explained that marmosets make
Speaker 1: excellent subjects in neurological research for several reasons. Quote, their
Speaker 1: shorter life span sixteen years in captivity means they reach
Speaker 1: adulthood more quickly, they have babies more quickly. Also, when
Speaker 1: you're studying neurogenerative disease like me, you need an older subject.
Speaker 1: A recis monkey, for example, isn't old until it's twenty
Speaker 1: five years old, but a marmoset has a shorter life span,
Speaker 1: so it essentially speeds up the pace of research. She
Speaker 1: says that marmoset's social cohesion they live in extended family
Speaker 1: groups of up to fifteen or so also helps ho
Speaker 1: stuff Works also spoke about email with doctor Tony Ziegler,
Speaker 1: distinguished scientist at the Center who focuses her study on
Speaker 1: that social order. Ziegler discovered that when a female marmoset
Speaker 1: gets pregnant, a male marmosets are primed to support their
Speaker 1: mate in a unique way. She said, marmosets in the
Speaker 1: wild and in captivity will ovulate within two weeks after
Speaker 1: giving birth and conceive over eighty five percent of the time.
Speaker 1: The mom is in a cycle of a five month gestation,
Speaker 1: and there are just two weeks out of the year
Speaker 1: that she's not pregnant and Marmosets are multiple ovulators. They
Speaker 1: give birth to twins and triplets in captivity, not really
Speaker 1: in the wild. The twins can weigh twenty percent of
Speaker 1: the mother's body weight, so they are a huge energetic
Speaker 1: load and the mother needs helpers. The males are actually
Speaker 1: going through hormonal changes along with their mates. It's likely
Speaker 1: they're getting chemical signal communication that the mate is pregnant,
Speaker 1: and they'll gain weight as the mate does during the pregnancy,
Speaker 1: and they start having hormonal changes things like the estrogen
Speaker 1: prolactin glucocorticoid changes, which is like cortisol before the babies
Speaker 1: are born. Ziegler says that experiments in which sixty percent
Speaker 1: of marmoset fathers went searching for their offspring when hearing
Speaker 1: their recorded cry led her to believe that those marmoset
Speaker 1: fathers had been better primed for fatherhood with their mates
Speaker 1: and had better social bonding. As Ziegler said, marmosets are
Speaker 1: great to work with. Their whole social system is amazing.
Speaker 1: They're very curious, they love people. They love to observe
Speaker 1: people as much as people love to observe them. It
Speaker 1: makes for a great species to work with. Although responsible
Speaker 1: Animal research is an important part of medical research that
Speaker 1: can save and improve many lives. Marmosets do not make
Speaker 1: good pets. They thrive when they're housed with their family members.
Speaker 1: Captive marmosets can get bored and require the right sort
Speaker 1: of stimulation and activity, which is truly a full time
Speaker 1: job for researchers who work with them to provide in
Speaker 1: those rare circumstances where they are kept in captivity. Today's
Speaker 1: episode is based on an article marmosets are tiny upper
Speaker 1: canopy dwelling monkeys on how Stuffworks dot Com written by
Speaker 1: Patti Rasnesen. Brain Stuff is production of by Heart Radio
Speaker 1: in partnership with how stuffworks dot Com and is produced
Speaker 1: by Tyler Klang. Four more podcasts from my heart Radio,
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