1 00:00:01,840 --> 00:00:07,680 Speaker 1: Welcome to brainstuff, a production of iHeartRadio, Hey brain Stuff 2 00:00:07,760 --> 00:00:14,400 Speaker 1: Lauren Vogelbaum here. Reproduction is a weird and multitudinous process. 3 00:00:14,440 --> 00:00:17,319 Speaker 1: Some fish, for example, release their eggs into the water 4 00:00:17,520 --> 00:00:20,960 Speaker 1: to be fertilized without any direct contact between either parent. 5 00:00:21,880 --> 00:00:24,919 Speaker 1: Some living creatures don't need two parents at all, like 6 00:00:25,079 --> 00:00:28,040 Speaker 1: yeast's the kind we use to make bread that reproduce 7 00:00:28,080 --> 00:00:30,920 Speaker 1: by a new organism butting right off of a single parent, 8 00:00:31,560 --> 00:00:34,960 Speaker 1: or mushrooms that release spores which are like seeds, except 9 00:00:35,000 --> 00:00:37,239 Speaker 1: they don't need to be pollinated to develop into a 10 00:00:37,280 --> 00:00:40,600 Speaker 1: new mushroom. Even some lizards have been known to lay 11 00:00:40,600 --> 00:00:43,680 Speaker 1: eggs that develop into a hatchling without having been fertilized. 12 00:00:45,280 --> 00:00:48,280 Speaker 1: But in most of the higher animal kingdom, a male 13 00:00:48,320 --> 00:00:51,600 Speaker 1: animal delivers its sex cells or sperm to a female animal, 14 00:00:51,800 --> 00:00:54,520 Speaker 1: which keeps its sex cells or eggs inside its body, 15 00:00:54,840 --> 00:00:57,320 Speaker 1: where the young are nourished and developed until the female 16 00:00:57,320 --> 00:01:03,520 Speaker 1: animal gives birth. However, not so for seahorses. Male seahorses 17 00:01:03,680 --> 00:01:09,039 Speaker 1: carrie and birth they're young seahorses. Sea dragons and pipefishes 18 00:01:09,080 --> 00:01:11,840 Speaker 1: are a family of small marine fishes that tend to 19 00:01:11,840 --> 00:01:15,720 Speaker 1: have bony armour and long snouts with fused jaws. They 20 00:01:15,760 --> 00:01:18,840 Speaker 1: also have the unusual habit of leaving the gestation of 21 00:01:18,880 --> 00:01:21,760 Speaker 1: their young to the males. They do this in a 22 00:01:21,920 --> 00:01:25,039 Speaker 1: uterus like pouch, a complete with a placenta found in 23 00:01:25,120 --> 00:01:29,360 Speaker 1: their tails. A male seahorses have this pouch on the 24 00:01:29,360 --> 00:01:32,800 Speaker 1: front of their tails. The female seahorse impregnates the male 25 00:01:32,880 --> 00:01:35,720 Speaker 1: by inserting eggs into that pouch, into which the male 26 00:01:35,760 --> 00:01:38,880 Speaker 1: releases sperm to fertilize the eggs, and then incubates the 27 00:01:38,880 --> 00:01:42,600 Speaker 1: babies for twenty four days. Researchers have found that they 28 00:01:42,640 --> 00:01:45,840 Speaker 1: even provide the developing young with oxygen and nutrients during 29 00:01:45,880 --> 00:01:51,080 Speaker 1: this time, like female mammals and some reptiles do. The 30 00:01:51,120 --> 00:01:54,520 Speaker 1: mechanism behind this process of labor and birth was mysterious 31 00:01:54,520 --> 00:01:57,680 Speaker 1: for a long time, but an Australian research team has 32 00:01:57,720 --> 00:02:00,960 Speaker 1: cested out in a study published in September of twenty 33 00:02:00,960 --> 00:02:04,320 Speaker 1: twenty two in the journal Placenta. The researchers reported that 34 00:02:04,360 --> 00:02:07,040 Speaker 1: male seahorses labor and give birth in a way that's 35 00:02:07,200 --> 00:02:12,040 Speaker 1: very different from other mothers. Female labor in birth is 36 00:02:12,120 --> 00:02:15,920 Speaker 1: driven primarily by hormones like oxytocin, which can tract the 37 00:02:15,960 --> 00:02:18,680 Speaker 1: smooth muscles of the uterus to push the babies out. 38 00:02:19,560 --> 00:02:23,560 Speaker 1: A smooth muscle tissue works involuntarily, whereas skeletal muscles can 39 00:02:23,639 --> 00:02:26,600 Speaker 1: flex and relax when the brain tells them to, which 40 00:02:26,600 --> 00:02:29,519 Speaker 1: is why you can probably smile at will, but people 41 00:02:29,560 --> 00:02:33,880 Speaker 1: can't go into labor whenever they want. The research team 42 00:02:33,919 --> 00:02:36,560 Speaker 1: found the muscle tissue of the seahorse brood pouch did 43 00:02:36,560 --> 00:02:39,920 Speaker 1: not respond to the fish version of oxytocin, but that 44 00:02:40,000 --> 00:02:44,120 Speaker 1: the pouch itself contained very little smooth muscle tissue. Instead, 45 00:02:44,360 --> 00:02:47,200 Speaker 1: they found that the male seahorse has three small bones 46 00:02:47,240 --> 00:02:49,200 Speaker 1: at the opening of the brood pouch, where the anal 47 00:02:49,240 --> 00:02:53,119 Speaker 1: fin attaches to these skeletal muscles. Female seahorses have very 48 00:02:53,120 --> 00:02:56,240 Speaker 1: small or not existent anal fins. They are more prominent 49 00:02:56,280 --> 00:03:00,480 Speaker 1: in males. It turns out that those anal fins and 50 00:03:00,520 --> 00:03:03,080 Speaker 1: the skeletal muscles that power them are a key to 51 00:03:03,120 --> 00:03:05,880 Speaker 1: the mystery of seahorse birth, as they play a role 52 00:03:05,919 --> 00:03:09,799 Speaker 1: in both mating and labor for the seahorse. During courtship, 53 00:03:09,840 --> 00:03:12,440 Speaker 1: the male seahorse does a little sit up style dance, 54 00:03:12,680 --> 00:03:15,639 Speaker 1: a crunching and expanding his abdomen to let water into 55 00:03:15,680 --> 00:03:18,280 Speaker 1: his brood pouch. He does the same thing when he 56 00:03:18,320 --> 00:03:21,880 Speaker 1: goes into labor, pressing and relaxing his abdomen until his 57 00:03:22,080 --> 00:03:27,200 Speaker 1: thousands of babies few fourth. So instead of smooth muscle 58 00:03:27,280 --> 00:03:30,520 Speaker 1: running the seahorse birthing show, it's the skeletal muscles of 59 00:03:30,520 --> 00:03:32,880 Speaker 1: the amal fin the contract to open the brood pouch 60 00:03:32,919 --> 00:03:36,160 Speaker 1: of the male seahorse. More study is required to test 61 00:03:36,160 --> 00:03:39,680 Speaker 1: whether seahorses consciously make the contractions happen, or if the 62 00:03:39,720 --> 00:03:43,280 Speaker 1: skeletal muscles somehow override their normal rules and contract on 63 00:03:43,320 --> 00:03:47,280 Speaker 1: their own. A seahorse father can give birth to as 64 00:03:47,280 --> 00:03:50,720 Speaker 1: many as two thousand babies at a time. The scientists 65 00:03:50,800 --> 00:03:52,880 Speaker 1: think the reason that males give birth instead of the 66 00:03:52,880 --> 00:03:56,640 Speaker 1: females is because seahorse babies are often eaten by predators, 67 00:03:57,080 --> 00:03:59,600 Speaker 1: and so having the male give birth allows the female 68 00:03:59,640 --> 00:04:02,240 Speaker 1: time to create more eggs to be fertilized without having 69 00:04:02,280 --> 00:04:05,840 Speaker 1: to wait to give birth herself, sharing that labor insures 70 00:04:05,880 --> 00:04:14,360 Speaker 1: survival the species. Today's episode is based on the article Yes, 71 00:04:14,480 --> 00:04:17,920 Speaker 1: malsea horses do give birth Here's how on HowStuffWorks dot Com, 72 00:04:17,960 --> 00:04:21,200 Speaker 1: written by Jesslin Shields. Brainstuff is production by Heart Radio 73 00:04:21,320 --> 00:04:23,680 Speaker 1: in partnership with HowStuffWorks dot Com and is produced by 74 00:04:23,720 --> 00:04:26,920 Speaker 1: Tyler Klang. Four more podcasts from my heart Radio. Visit 75 00:04:26,960 --> 00:04:29,880 Speaker 1: the iHeartRadio app, Apple Podcasts, or wherever you listen to 76 00:04:29,880 --> 00:04:30,799 Speaker 1: your favorite shows.