1 00:00:01,840 --> 00:00:07,280 Speaker 1: Welcome to brain Stuff, a production of iHeartRadio, Hey brain 2 00:00:07,280 --> 00:00:13,680 Speaker 1: Stuff Lauren Vogelbaum here Curious, Lively and social. Common Marmosets 3 00:00:13,760 --> 00:00:16,920 Speaker 1: are a group of monkeys found primarily in the forested 4 00:00:16,960 --> 00:00:21,200 Speaker 1: areas of central Brazil and neighboring areas of South America. 5 00:00:21,320 --> 00:00:24,480 Speaker 1: There are more than twenty subspecies of marmosets, including the 6 00:00:24,520 --> 00:00:28,360 Speaker 1: pygmy marmoset, which is the world's smallest monkey. It weighs 7 00:00:28,400 --> 00:00:31,360 Speaker 1: on average just over four ounces that's about one hundred 8 00:00:31,360 --> 00:00:34,199 Speaker 1: and twenty grams and measures just over five inches in 9 00:00:34,280 --> 00:00:39,559 Speaker 1: length or about twelve centimeters. Marmosets are members of one 10 00:00:39,640 --> 00:00:44,199 Speaker 1: of five families of primates called Plattarines or New World monkeys. 11 00:00:45,080 --> 00:00:48,239 Speaker 1: That's because at some point millions of years ago they 12 00:00:48,280 --> 00:00:51,040 Speaker 1: separated from the primates of Africa and wound up on 13 00:00:51,080 --> 00:00:54,240 Speaker 1: the other side of the Atlantic. The apes and so 14 00:00:54,360 --> 00:00:59,960 Speaker 1: called Old World monkeys are catarines. Marsets are almost exclusively 15 00:01:00,120 --> 00:01:04,600 Speaker 1: tree dwellers. Their nostrils are rounded and further apart than catarines, 16 00:01:04,959 --> 00:01:07,840 Speaker 1: and though they do use their tails for balance, their 17 00:01:07,880 --> 00:01:11,960 Speaker 1: tails are not prehensile, meaning they can't grasp things with them. 18 00:01:13,400 --> 00:01:17,360 Speaker 1: Those tails are banded and long, usually longer than their bodies. 19 00:01:18,280 --> 00:01:21,680 Speaker 1: Even non pygmy types are pretty small. The average male 20 00:01:21,720 --> 00:01:25,000 Speaker 1: marmoset weighs about nine ounces or two hundred and fifty grams, 21 00:01:25,120 --> 00:01:27,399 Speaker 1: and will be just over seven inches in length that's 22 00:01:27,400 --> 00:01:31,960 Speaker 1: about eighteen centimeters. Females are just a little smaller. Their 23 00:01:31,959 --> 00:01:34,400 Speaker 1: facial skin is pale, but it darkens in the sun. 24 00:01:35,200 --> 00:01:38,200 Speaker 1: They're covered with fur that's flecked with brown, gray, and yellow. 25 00:01:38,880 --> 00:01:41,720 Speaker 1: They have large white ear tufts and the white blaze 26 00:01:41,760 --> 00:01:46,280 Speaker 1: on their forehead. Their hands and feet look very similar 27 00:01:46,280 --> 00:01:49,880 Speaker 1: to squirrels. Their thumbs are not opposable, and they have 28 00:01:50,000 --> 00:01:53,280 Speaker 1: claw like nails on all but their big toe. They 29 00:01:53,360 --> 00:01:56,240 Speaker 1: use these claws to help them move through the trees quickly, 30 00:01:56,480 --> 00:01:59,960 Speaker 1: using all four legs like squirrels, but also to scrap 31 00:02:00,200 --> 00:02:02,720 Speaker 1: and scratch tree bark to get at the gums, app 32 00:02:02,760 --> 00:02:04,960 Speaker 1: and resin that can make up to seventy percent of 33 00:02:04,960 --> 00:02:11,680 Speaker 1: their diet. Marmosets also forage four insects and eat fruit, seeds, fungi, nectar, 34 00:02:11,960 --> 00:02:17,600 Speaker 1: and small animals from snails to lizards to nestlings. They're 35 00:02:17,639 --> 00:02:21,280 Speaker 1: active for eleven to twelve hours a day after feeding 36 00:02:21,360 --> 00:02:24,520 Speaker 1: for an hour or so after waking, marmosets typically alternate 37 00:02:24,560 --> 00:02:28,880 Speaker 1: between resting, feeding, and socializing with their family group. According 38 00:02:28,880 --> 00:02:32,359 Speaker 1: to researchers, fifty three percent of their time is spent stationary, 39 00:02:32,919 --> 00:02:37,760 Speaker 1: sprawled out like their on summer vacation, but it's not 40 00:02:37,960 --> 00:02:41,080 Speaker 1: all rolling around the treetops. Being on the small side 41 00:02:41,080 --> 00:02:45,680 Speaker 1: means marmosets are particularly vulnerable to predators, especially raptors and owls, 42 00:02:45,960 --> 00:02:50,600 Speaker 1: tree snakes, wildcats, and mustelids like weasels, badgers, and ferrets. 43 00:02:51,680 --> 00:02:53,760 Speaker 1: In the wild. The average life span of the Carmen 44 00:02:53,800 --> 00:02:59,040 Speaker 1: marmoset is twelve years. For the article, this episode is 45 00:02:59,080 --> 00:03:02,160 Speaker 1: based on to Works checked in with the Wisconsin National 46 00:03:02,200 --> 00:03:06,640 Speaker 1: Primate Research Center at the University of Wisconsin Madison. The 47 00:03:06,680 --> 00:03:09,440 Speaker 1: center is currently home to about two hundred and seventy 48 00:03:09,480 --> 00:03:13,120 Speaker 1: marmosets who are helping researchers learn more about everything from 49 00:03:13,320 --> 00:03:19,280 Speaker 1: parenting to Parkinson's disease. Specifically, Hastiff Works spoke by email 50 00:03:19,360 --> 00:03:22,760 Speaker 1: with doctor Marina Emborg, a medical doctor, a professor of 51 00:03:22,800 --> 00:03:26,440 Speaker 1: medical physics, and the director of the pre clinical Parkinson's 52 00:03:26,480 --> 00:03:31,040 Speaker 1: Research program at the center. She explained that marmosets make 53 00:03:31,120 --> 00:03:36,240 Speaker 1: excellent subjects in neurological research for several reasons. Quote, their 54 00:03:36,320 --> 00:03:39,520 Speaker 1: shorter life span sixteen years in captivity means they reach 55 00:03:39,560 --> 00:03:44,000 Speaker 1: adulthood more quickly, they have babies more quickly. Also, when 56 00:03:44,040 --> 00:03:48,480 Speaker 1: you're studying neurogenerative disease like me, you need an older subject. 57 00:03:49,200 --> 00:03:52,600 Speaker 1: A recis monkey, for example, isn't old until it's twenty 58 00:03:52,600 --> 00:03:55,560 Speaker 1: five years old, but a marmoset has a shorter life span, 59 00:03:55,920 --> 00:04:01,600 Speaker 1: so it essentially speeds up the pace of research. She 60 00:04:01,720 --> 00:04:05,440 Speaker 1: says that marmoset's social cohesion they live in extended family 61 00:04:05,480 --> 00:04:09,360 Speaker 1: groups of up to fifteen or so also helps ho 62 00:04:09,440 --> 00:04:12,360 Speaker 1: stuff Works also spoke about email with doctor Tony Ziegler, 63 00:04:12,560 --> 00:04:15,720 Speaker 1: distinguished scientist at the Center who focuses her study on 64 00:04:15,800 --> 00:04:20,400 Speaker 1: that social order. Ziegler discovered that when a female marmoset 65 00:04:20,480 --> 00:04:24,120 Speaker 1: gets pregnant, a male marmosets are primed to support their 66 00:04:24,160 --> 00:04:28,919 Speaker 1: mate in a unique way. She said, marmosets in the 67 00:04:28,920 --> 00:04:32,120 Speaker 1: wild and in captivity will ovulate within two weeks after 68 00:04:32,160 --> 00:04:35,680 Speaker 1: giving birth and conceive over eighty five percent of the time. 69 00:04:36,440 --> 00:04:38,920 Speaker 1: The mom is in a cycle of a five month gestation, 70 00:04:39,240 --> 00:04:41,320 Speaker 1: and there are just two weeks out of the year 71 00:04:41,400 --> 00:04:46,320 Speaker 1: that she's not pregnant and Marmosets are multiple ovulators. They 72 00:04:46,360 --> 00:04:49,360 Speaker 1: give birth to twins and triplets in captivity, not really 73 00:04:49,440 --> 00:04:52,440 Speaker 1: in the wild. The twins can weigh twenty percent of 74 00:04:52,480 --> 00:04:55,240 Speaker 1: the mother's body weight, so they are a huge energetic 75 00:04:55,279 --> 00:04:59,080 Speaker 1: load and the mother needs helpers. The males are actually 76 00:04:59,120 --> 00:05:03,400 Speaker 1: going through hormonal changes along with their mates. It's likely 77 00:05:03,440 --> 00:05:06,440 Speaker 1: they're getting chemical signal communication that the mate is pregnant, 78 00:05:06,760 --> 00:05:09,680 Speaker 1: and they'll gain weight as the mate does during the pregnancy, 79 00:05:10,080 --> 00:05:13,839 Speaker 1: and they start having hormonal changes things like the estrogen 80 00:05:13,920 --> 00:05:18,400 Speaker 1: prolactin glucocorticoid changes, which is like cortisol before the babies 81 00:05:18,400 --> 00:05:25,240 Speaker 1: are born. Ziegler says that experiments in which sixty percent 82 00:05:25,279 --> 00:05:28,360 Speaker 1: of marmoset fathers went searching for their offspring when hearing 83 00:05:28,360 --> 00:05:31,760 Speaker 1: their recorded cry led her to believe that those marmoset 84 00:05:31,839 --> 00:05:34,800 Speaker 1: fathers had been better primed for fatherhood with their mates 85 00:05:34,920 --> 00:05:40,160 Speaker 1: and had better social bonding. As Ziegler said, marmosets are 86 00:05:40,200 --> 00:05:43,400 Speaker 1: great to work with. Their whole social system is amazing. 87 00:05:43,880 --> 00:05:47,400 Speaker 1: They're very curious, they love people. They love to observe 88 00:05:47,440 --> 00:05:50,320 Speaker 1: people as much as people love to observe them. It 89 00:05:50,360 --> 00:05:56,520 Speaker 1: makes for a great species to work with. Although responsible 90 00:05:56,560 --> 00:05:59,640 Speaker 1: Animal research is an important part of medical research that 91 00:05:59,680 --> 00:06:03,960 Speaker 1: can save and improve many lives. Marmosets do not make 92 00:06:04,000 --> 00:06:08,039 Speaker 1: good pets. They thrive when they're housed with their family members. 93 00:06:08,440 --> 00:06:11,920 Speaker 1: Captive marmosets can get bored and require the right sort 94 00:06:11,960 --> 00:06:15,360 Speaker 1: of stimulation and activity, which is truly a full time 95 00:06:15,440 --> 00:06:18,040 Speaker 1: job for researchers who work with them to provide in 96 00:06:18,200 --> 00:06:27,039 Speaker 1: those rare circumstances where they are kept in captivity. Today's 97 00:06:27,040 --> 00:06:29,960 Speaker 1: episode is based on an article marmosets are tiny upper 98 00:06:30,000 --> 00:06:32,760 Speaker 1: canopy dwelling monkeys on how Stuffworks dot Com written by 99 00:06:32,800 --> 00:06:35,800 Speaker 1: Patti Rasnesen. Brain Stuff is production of by Heart Radio 100 00:06:35,920 --> 00:06:38,200 Speaker 1: in partnership with how stuffworks dot Com and is produced 101 00:06:38,200 --> 00:06:41,239 Speaker 1: by Tyler Klang. Four more podcasts from my heart Radio, 102 00:06:41,520 --> 00:06:44,640 Speaker 1: visit the iHeartRadio app, Apple Podcasts, or wherever you listen 103 00:06:44,680 --> 00:06:45,679 Speaker 1: to your favorite shows.