Why is Australia's big herbivore so strange?

Across the world all the continents and ecological regions have their own large herbivore like bison, elephants, or the guonacos and tapirs in south America. Despite the many differences between each of the continents largest animals, they are all at least partly hoofed, four legged and move around by walking or galloping. However, in Australia the largest animal on the continent is the kangaroo which is none of these things so why did Australia's largest herbivore evolve so differently to every where else?

If I have used artwork that belongs to you but have neglected to credit it this will just be because I was unable to find one. If this has happened please contact me and I will add a credit. Some Art work has been altered for the purposes of bettering them for video format; these alterations were done independent from the artists who created the original work, so they are not responsible for any inaccuracies that could have occurred with the changes being made.

Sources:

[peterskye]

Part of the efficiency of hopping in macropods comes from their heavy and muscular tail, which provides a perfect counterbalance for the hopping movement.

[lightsoda]

Fun fact, both the Kangaroo and the Emu cannot move backwards. Hence why they were both chosen to be on the Australian coat of arms as a symbol of always moving forward.

[powpuckmobile]

There's also their method of reproduction as a factor. Marsupial young need to climb to reach their mother's pouch, and thus need grasping forepaws. This prevents specialized cursorial traits such as hooves from being selected for.

[benprint]

As someone who was born in England and raised there until I was 11 in which I then moved to Australia, Kangaroos still baffle me 12 years later. Sure I’m used to them now, but they’re still unlike any other mammal. I will never forget walking to the bus stop for school in the mornings and having a pack of kangaroos sunbathing on my lawn every morning. We used to feed them weetbix and they’d come right up to the patio undercover when it rained.

[bkjeong]

It is important to realize that Australia actually had a much wider array of large animals even up until human colonization (and an even greater array around half a million years ago). We should not be considering Australia as being evolutionarily or ecologically different from other continents for lacking large animals, because modern Australian ecosystems actually developed in the context of having large terrestrial animals.

Even after Australia underwent desertification there were still over a dozen species of large terrestrial megafauna left by the time humans arrived on the continent. Diproton was was one of them.

[sylviaelse]

Near where I live in Australia, there are wallabies that seem to find no difficulty moving around terrain that is both steep, wooded, and rocky. Certainly terrain that I, as a non-hopping biped, would find challenging.

[amphicyon]

One thing I love about this channel is that it goes into much more depth than other animal related media. Most other shows, channels and articles would end around 6:09, but Moth Light manages to continue asking questions to give a more complete picture.

Keep up the great work my man!

[lachlanbell]

Pretty much all the things people find strange about Australian wildlife can be distilled down to the same basic survival pressure of inhabiting a vast continent full of open space, yet mostly semi-arid with very little rainfall and sparse nutrition. It's the same reason that everything here is so goddamn venomous: any snake or spider that encounters a prey item needs to capitalise on that opportunity ASAP, and they can't afford to risk their prey getting away, or inflicting insufficient damage to kill them. Hence they all evolved to have ultra-potent venom, and lots of it, to ensure that when they got the opportunity to attack, they were able to kill very quickly and reliably. Australian snake venom can kill a rodent or similar in a fraction of the time it takes for most snakes in other places, which means that prey item isn't going anywhere. If they miss that one, who even knows when the next chance might present itself. You can't afford to take that chance. Also why kangaroos hop, and why koalas barely move and spend like 22 hours a day sleeping.

[bungalo]

maybe a factor in the evolution of this trait would be that standing up gave the kangaroos a longer vision distance, which would be well suited for a flat continent like Australia

[RiiftApart]

Hey man, I just wanted to say that we really appreciate your work. Pursuing knowledge about Evolution, interesting as it might be, is often not easy and not very accessible, so you making it more available for everyone is a huge gift. Thanks for everything!

P.S.- What is the name of some of the themes used here, such as in Flying Reptiles? I absolutely adore them and can’t seem to find them.

[jandrews]

Kangaroos and their relatives have very efficient, sometimes considered TOO efficient, reproduction as a female can have one Joey at heel, another younger Joey in the pouch and a newborn as well. Her mammaries produce milk suitable for two different aged joeys at the one time.

[davidgriffiths]

Also the ground gets very hot, less time spent in contact with the ground would mean animals can move more quickly during the day instead of waiting in the shade of rocks or trees for the ground to be cool enough to stand on. At cruising speed they would spend about 90% of the time in the air allowing their feet to keep cool enough to travel across hot ground without injury. I have also found a likely solution for the giant tunnelling sloths, the tunnels were to protect slow moving juveniles until they are large enough to survive predation….

[avizinder]

Bipedal stances raise the body and head higher off the ground, which can be deadly hot in arid environments. Maybe this is why bipedal mammals are common in these environments. Or maybe it lets them see predators from further away.

[benvandusen]

Efficient hopping might also result in less breathing, thus conserving water.

[VasanthSesh]

The first settlers in Australia upon seeing a kangaroo: I’ve never seen herbivore!

[Alan]

This is ridiculously high quality for such few views. You have a bright YouTube future ahead!!

[austinhinton]

Given the tendency for hopping to evolve in arid environments (or that hopping just happened to work good in aridity) I wonder if living in a place where food sources were few and far between, allowed hoppers to more effectively and quickly move from one food source to another? That hopping let you hit more shrubs before your non-hopping competitors. Whereas environments that had more abundant and evenly distributed food sources, hopping didn’t offer any really advantage, so hoppers aren’t as common in those environments. About the only hoppers that live in such places I can think of are rabbits.

[JohnDrummondPhoto]

If Procoptodon couldn't hop, how did it actually walk? Kangaroos actually hop on their toes, and the kangaroo rat at 7:25 is walking bipedally on its toes. So maybe Procoptodon did too. That would explain that one giant toe on each foot, which would function like the foot of an ostrich

[MrSaemichlaus]

What I love about this channel is that it drops right into the specifics of the topic and many of the comments provide useful context or additional info.

[magnetshowdotheywork]

Roos use their front paws like 90% of the time from my experience. They’re built extremely well for the Aussie terrain.