Kangaroos Are Pure Muscle

Would you look at these bouncing beauties! My deepest apologies to koalas, crocodile Dundee, and Chris Hemsworth, but the honour of most iconic Australian obviously goes to these furry marsupial cuties. Let's hop to it and jump feet first into the wonderful world of kangaroos and wallabies. Hi, I'm Danielle Dufault and you're watching Animalogic. Today we're on Moriah Island in Tasmania, just off the coast of the mainland. It's known to be a hot spot for a lot of endemic Tasmanian wildlife such as wombats, echidna, wallabies, patamelons, and even the Tasmanian devil. Wallabies are members of the genus Macropus. Wallaroos make up the genus Osphranter, and a kangaroo is basically just a name for a very large wallaby or wallaroo. They're all part of the macropod family. In ancient Greek, macropod roughly translates to bigfoot. Hmm, I wonder where they got that name? There are 10 different Macropus species. Some are kangaroos and some are wallabies. But what's the difference? Well, basically, it comes down to size. If you find yourself standing face-to-face with a macropus and they're below your eye level, you're probably hanging with a wallaby. They're the smallest. And if they're taller, it's a kangaroo. They're huge! And if your bud is somewhere between those two sizes, they're likely a wallaroo. Kind of the awkward middle child of the roo crew. Australia is obviously the number one macropus capital of the world. There are over 50 million kangaroos hopping around the mainland. That's almost two roos for every person! This boom is partly due to human interference. Early settlers drove almost all of their natural predators to extinction and transformed some of that harsh Australian brush into more macropus-friendly landscapes. But some Australians think of them as pests because they destroy crops and cause car accidents by hopping into the road. But hey, they were here first, humans. Respect the roo. Even though kangaroos pack a killer kick, they likely won't bite. They're herbivores. They don't even have canine teeth. Luckily, their molars are strong enough to crush up plant matter. Like cows and other ruminants, they regurgitate and chew their food twice. Then they use the bacteria and fungi in the separate chambers of their very complex digestive system to turn bland greens into yummy nutrients. But enough about diet and geography and genus. You're here for one reason and one reason only. The hopping! Frogs and bunnies have nothing on these legendary hoppers. The best kangaroo jumps can take them two meters forward, three meters high, and reach speeds of 60 kilometers an hour. So I gotta say, this is the first time that I've interacted with a mammal who is also bipedal, aside from other humans, of course. This is something that we share in common with these guys, with these very specialized feet. They can hop and jump and run at high speeds and prop themselves up with their tail and their front paws when they need to. These animals are such expert bouncers that they actually conserve energy when hopping far distances at high speeds. The tendons in their legs act like springs. When they land, the tendons get compressed and then want to expand again right away. So the energy is mostly coming from their tendons, not their muscles. To handle these high-speed hops, macropus developed muscular tails that keep them balanced. Their tails also help propel them forward for jumps. Think of it as their third leg. Their breathing is synchronized with their bouncing. When they jump, their lungs automatically empty, and when they land, their lungs fill with air. There's a lot of power behind those hops. Being able to hop very quickly across vast distances and turn locale plants into energy are the reasons kangaroos and wallabies do well in the Australian desert. Very few large mammals would be able to survive that barren environment, let alone thrive in it. The most powerful macropods are, of course, kangaroos. The red kangaroo is the largest. They can grow up to two meters tall and weigh 90 kilograms. They're members of the Osphranter genus, so they're more closely related to wallaroos than to other kangaroos. But how can we ignore this muscly macropod beast? These are the dudes that look like they ate a bowl of steroids for breakfast. Red kangaroos also love socializing. They've been spotted hanging out in groups as big as a thousand. Popular and beefy, these guys are total jocks. Former threats like the Tasmanian tiger and marsupial lion have gone extinct, so red kangaroos don't have any predators. But the baby joeys can be snatched up by eagles or dingoes. Here's where I could make a dingo ate my baby joke, but I won't subject you to my Australian accent. 2020 has been tough enough. The second biggest kangaroo after the red is the eastern grey. These kangaroos are just as tall as the red, but much thinner. They're super comfortable with humans, because they happen to enjoy the same climate and land conditions as we do. Eastern grey kangaroos also enjoy socializing, but only in groups of ten or less. Far more exclusive than a thousand. By the way, a group of kangaroos is called a mob, so stay on their good side and never ask them about their business. These are the kangaroo island kangaroos. As this species evolved on an island environment, they didn't really have any natural predators to face out there, so naturally they became a little bit less fearful. They didn't really develop that kind of anxious response too much, because they didn't have to worry about natural predators. They became almost like a pygmy kangaroo. Being on an island, you tend to evolve to be smaller, and became more social, because you had to deal with your neighbours. Gotta get friendly. Then there's the wallaby. They're smaller and more solitary than their kangaroo cousins. This is a swamp wallaby. They don't necessarily live near swamps, but they sure do smell like they do. That's where they get their nickname, Stinker. There are several different wallaby species, and some have actually been successfully introduced to areas outside of Australia, including Hawaii, France, New Zealand, and the UK. Who knew wallabies were so worldly? If you're really lucky, you might come across one of the most beautiful members of the kangaroo family, the white wallaby. Off the southeast coast of Tasmania, on Bruny Island, there lives a colony of about 200 albino wallabies. This genetic mutation makes them sensitive to the sun, gives them poor eyesight, and makes them stick out like a sore thumb. Fortunately, their island is free of natural predators, allowing the white wallaby's population to thrive. Since kangaroos, wallabies, and the frequently forgotten wallaroos are all marsupials, they carry their newborns in pouches. After just one month of pregnancy, the mother gives birth to a blind baby joey that weighs just one gram. Despite their tiny size and general uselessness, the joey's sense of smell and strong arms help them climb up their mama's body and into her pouch, where they'll stay for five to eleven months. Oh, I can see it. He's kind of hanging to, uh, just to the right. This, this little lady is pregnant with a little joey inside. So she's got to eat lots to help him grow big and strong. There's only room for one joey in one pouch. Highlander rules. So no litters or even twins. Macropods can do something pretty cool called embryonic diapause. It means she can delay the development of a fertilized egg if her pouch is already filled with a joey. When that joey gets old enough to leave her pouch, or if he dies, she can choose to fertilize her banked egg and start the process again. That'd be too convenient. So how do we become marsupials? I think we've missed the mark by a few million years, but... Once the joey is over the pouch stage, he'll still need to stay close to mom. She provides all his food and he'll eat directly out of her pouch. After a few months, the little kangaroo is weaned off her milk. And finally, at the very grown-up age of three, he is sexually mature. Mazel Tov! If he looks both ways before crossing the road, this kangaroo could spend a nice long life soaking up the Australian sun, feasting on leafy greens, and hopping to his heart's content. Have fun, Mr. Macropus! So what should I talk about next? Please let me know in the comments, and don't forget to subscribe for new episodes every week. Thanks for watching! See ya!