Speaker 1: Welcome to Brainstuff, a production of iHeartRadio, Hey brain Stuff
Speaker 1: Lauren Vohlabam. Here travel back in time around four thousand
Speaker 1: years to a remote Russian Arctic island, and you might
Speaker 1: see a few shaggy brown quadrupeds with trunks tugging up
Speaker 1: tufts of grassy ground cover and shoving them into their
Speaker 1: tusked mouths. But despite their four stout legs and thin
Speaker 1: whipping tails, you would never mistake them for hairy elephants.
Speaker 1: Sure if your glasses broke on the trip, you might
Speaker 1: miss the distinctive downward slope of their backs, the finger
Speaker 1: like grippers on the ends of their trunks, and their small,
Speaker 1: cold adapted tail and ears. But no amount of astigmatism
Speaker 1: could make you miss the fact that these animals aren't
Speaker 1: much taller than you. You have found the Wrangel Island mammoths,
Speaker 1: the dwarf descendant of the wooly mammoth. They are the
Speaker 1: last of their Kindlike the twenty five percent larger woolies
Speaker 1: that in their heyday numbered in the several millions across
Speaker 1: Eurasia and North America, these diminutive descendants survived the roughly
Speaker 1: north to south Domino of extinction that had finished off
Speaker 1: so many large mammals more than six thousand years earlier.
Speaker 1: They walked Wrangle Island when humans were building pyramids in
Speaker 1: Egypt and constructing Stonehenge in Great Britain, but soon, perhaps
Speaker 1: done in by the same forces that killed their ancestors,
Speaker 1: a likely climate change, human hunting, or some combination of
Speaker 1: the two, time would catch up with them as well.
Speaker 1: We probably know more about wooly mammoths and mammos in
Speaker 1: general than we do about any other extinct species. Compared
Speaker 1: to the last dinosaurs, which died out around sixty five
Speaker 1: million years ago, Mammoths only recently shuffled off this mortal coil,
Speaker 1: recently enough that ancient humans hunted them, ate them, used
Speaker 1: their ivory for tools, and depicted them in some of
Speaker 1: the earliest known sculpture in cave art. They are well
Speaker 1: preserved remains, which at times consist of complete carcasses, pickled
Speaker 1: and frozen anaerobic soils can contain muscle, blood, teeth, bone, tusk,
Speaker 1: and even brain. We've even recovered and sequenced mammoth DNA.
Speaker 1: What's more, we have three living, albeit distant cousins to
Speaker 1: compare them with the African bush and African forest elephant,
Speaker 1: and the Asian elephant, which is the mammoth's closest living relative.
Speaker 1: By combining what we know about modern elephants with evidence
Speaker 1: from the wooly mammth fossils, preserved stool and gut contents,
Speaker 1: and other physical evidence, we can confidently paint a picture
Speaker 1: of what these wooly wonders were really like and how
Speaker 1: they worked. So today, let's jump back in that time
Speaker 1: machine and see what life was like when mammoths roamed
Speaker 1: the earth. Wooly mammoths roamed landscapes unlike any that exist today.
Speaker 1: During many parts of the Pleistocene, an epoch lasting from
Speaker 1: one point seven million to eleven thousand, five hundred years
Speaker 1: ago and ending with the most recent Ice Age, a
Speaker 1: mixture of rich and varied grasses, herbs, and sedges spread
Speaker 1: from Ireland to Siberia, across the Bearing Land Bridge and
Speaker 1: too much of modern Canada. This mammoth step was supported
Speaker 1: by a different climate. As growing glaciers locked up, water
Speaker 1: sea levels dropped, exposing great swaths of land dominated by
Speaker 1: clear and breezy blue skies. Grazing across this landscape in
Speaker 1: a twenty hour a day pursuit of food were vast
Speaker 1: numbers of wooly mammoths and creatures about the size of
Speaker 1: modern elephants. The males grazed alone, each standing around nine
Speaker 1: to eleven feet tall that's three to four meters and
Speaker 1: weighing about six tons. They ranged near matriarchal family groups
Speaker 1: of around ten to twenty smaller females and calves. They
Speaker 1: withstood the chill of their northern climes through number of adaptations,
Speaker 1: including a four inch layer of fat that's ten centimeters
Speaker 1: and an inch of thick oily skin. They had a
Speaker 1: wooly undercoat layered with coarser guard hairs ranging from a
Speaker 1: few inches up to three feet that's one meter long,
Speaker 1: with the longest hanging in a skirt along the animal's
Speaker 1: flanks and belly. Even their hemoglobin had heat retaining properties,
Speaker 1: a trait echoed in many modern cold adapted mammals. Wooly
Speaker 1: mammoths shared these lands with other massive mammals, including grazers
Speaker 1: like wily rhinoceros and long horde bison, and predators like
Speaker 1: sabertoothed cats and cave hyenas. Given their bulk and massive tusks,
Speaker 1: health the adult mammoths could take all comers in a fight,
Speaker 1: especially if gathered in a protective group, so predators likely
Speaker 1: preyed on sick or injured adults or picked off the
Speaker 1: occasional straggling calf. If, as experts suspect, mammoths were similar
Speaker 1: to today's elephants, then they were likely highly social, educating their
Speaker 1: cat and maybe even guarding and burying their dead. They
Speaker 1: may have periodically come together in great migratory herds and
Speaker 1: could probably swim to islands a few miles off shore.
Speaker 1: Mammoth calves were mostly born in spring, when fresh growth
Speaker 1: could support lactating mothers. A twenty two month gestation period
Speaker 1: meant that conception occurred in the late summer. The competing
Speaker 1: males would demonstrate their fitness via tusk displays, the ritualistic
Speaker 1: sparring or out and out fights. Beyond fighting, a mammoth's twisted,
Speaker 1: inward curling tusks were also handy for stripping and felling
Speaker 1: trees or shovel plowing through dirt and snow. Evolved from
Speaker 1: the mammoth's upper incisors, these tusks would grow throughout the
Speaker 1: animal's lifetime. The rest of its teeth consisted of foot
Speaker 1: long molars with side to side grooves that aided in
Speaker 1: breaking down its tough food. Like today's elephants, a mammoth
Speaker 1: would go through six sets of teeth in its sixty
Speaker 1: year lifespan, but typically dying after the last set wore out.
Speaker 1: A wooly mammoths are one of a number of large herbivores,
Speaker 1: including mastodons, elephants, and other mammoth species descended from the
Speaker 1: primitive Probosideans, named for a Greek word meaning nose, which
Speaker 1: all split off from the general ma million tree around
Speaker 1: fifty five million years ago. The first mammoths showed up
Speaker 1: in Africa around five to six million years ago, but
Speaker 1: they weren't wooly. The probable ancestor of the wooly mammoth,
Speaker 1: the step mammoth, may have originated in northeastern Eurasia around
Speaker 1: two million years ago. It was the largest of its kind,
Speaker 1: standing fourteen feet that's four point three meters and weighing
Speaker 1: at least ten tons. It sported smallish ears and tail,
Speaker 1: and a bit of a shaggy coat. Primarily a grazer,
Speaker 1: it also supplemented its diet with trees and shrubs. The
Speaker 1: comparatively smaller wooly mammoth, established around four hundred thousand years ago,
Speaker 1: likely resulted from specializations suited for the chill of Siberia,
Speaker 1: and it was from this ice box that botanist Michael
Speaker 1: Adams recovered the first wooly mammoth carcass in eighteen oh six.
Speaker 1: But the species spread as far as modern Ireland and
Speaker 1: crossed the Bering Strait to continue across Canada to the
Speaker 1: eastern coast of North America. Their population was highly adaptable
Speaker 1: to the fluctuations in climate that characterized the Pleistocene, yet
Speaker 1: within the brief period spanning from fourteen thousand to ten
Speaker 1: thousand years ago, they and most other large mammal species
Speaker 1: in the northern Hemisphere died out. But why Paleontologists have
Speaker 1: advanced several theories, including meteors, diseases, climate change, and human hunting,
Speaker 1: but there's no evidence of meteor strikes, and any potential
Speaker 1: disease that killed megafauna likely would have affected other animals too,
Speaker 1: so that leaves climate and hunting. According to the climate hypothesis,
Speaker 1: mammoth's very specialization that let them thrive in their step
Speaker 1: environment may have doomed them to isolization and starvation. As
Speaker 1: the climate shift melted glaciers and raised sea levels, cotton
Speaker 1: and shrength and wetter conditions prevailed. Their food sources dwindled,
Speaker 1: and mammoth populations declined with them. The hunting hypothesis emphasizes
Speaker 1: the fact that mammoths shockingly fast decline coincides with the
Speaker 1: generally accepted arrival of humans in North America from thirteen thousand,
Speaker 1: three hundred to twelve eight hundred years ago. We know
Speaker 1: that humans used mammoth firs, meat and ivory, and that
Speaker 1: both Neanderthals and Stone Age humans constructed buildings from mammoth bone,
Speaker 1: but many questions remain. Given that many humans could have
Speaker 1: survived on a single mammoth, especially aided by natural refrigeration,
Speaker 1: and that early humans venerated the animals in cave art,
Speaker 1: it's possible that they traded mammoths with the reverence and
Speaker 1: restraint that Native Americans had for buffalo. Either way, hunter
Speaker 1: gatherers likely had a varied diet and relied on small
Speaker 1: to medium game for meat, so how often they actually
Speaker 1: hunted mammoths versus scavenging their remains is unclear. Ultimately, the
Speaker 1: limitations of large mammals like mammoths, with their low birth
Speaker 1: rates and vast need for sustenance, might well have hastened
Speaker 1: to their end, worsening the effects of isolation, habitat, loss,
Speaker 1: and predation. But could we bring the wooly mammoth back?
Speaker 1: DNA is fragile and has a limited shelf life. We
Speaker 1: could never clone dinosaurs a la Jurassic Park, but given
Speaker 1: the excellent preservation and recent age of some mammoth remains,
Speaker 1: we could theoretically clone a mammoth or breed one through
Speaker 1: in vitro fertilization using elephant ovum modified or fertilized with
Speaker 1: mammoth genetic material. Both approaches entail complex ethical and practical concerns.
Speaker 1: After all, the environment that wooly mammoths lived in is gone,
Speaker 1: so where would they live? What would they be able
Speaker 1: to eat? If we bring them back just to keep
Speaker 1: them as curiosities and zoos? What kind of life is that?
Speaker 1: If we look at their living cousins, the elephants, they're
Speaker 1: a keystone species in their ecosystems. Their movements and activities
Speaker 1: create habitat for other animals and natural fire breaks, and
Speaker 1: their dung feeds. Numerous species spread seeds and changes the
Speaker 1: makeup of the soil. When an animal like that dies out,
Speaker 1: it sends thunderous impacts throughout the ecosystem, and bringing such
Speaker 1: an animal back would be equally thunderous. It seems more
Speaker 1: practical and more kind to focus on preserving the amazing
Speaker 1: species that we have alive today and honoring the extinct
Speaker 1: ones by further extinctions. Today's episode is based on the
Speaker 1: article how Wooly Mammoth's worked on how stuffworks dot com,
Speaker 1: written by Nicholas Jarbis. Brain Stuff is production by Heart
Speaker 1: Radio in partnership with how stuffworks dot Com, and it's
Speaker 1: produced by Tyler Klang. For more podcasts my heart Radio,
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