The Biology and People of Madagascar

in the 13th century the Italian Explorer Marco Polo claimed that there was a bird living in Madagascar that was so big and powerful that it could snatch up an elephant in its talons and fly away with it it is possible that the inspiration for this legendary bird of prey was a distorted account of a real bird that once lived in Madagascar or of its giant eggs there were 200 times the size of a chicken egg and may have been traded between sailors and Madagascan locals but these eggs were not laid by a large bird of prey Madagascar had no large grazing hoofed herbivores in his isolated ecosystem and instead a giant bird filled the niche of large herbivore the half a ton a pianist or because of Marco Polo story the elephant bird that weighed five times as much as an ostrich and was only one of many animals that showed how evolution had taken a different turn here Madagascar is separated from Africa by 250 miles of ocean which is about ten times the difference between Britain and mainland Europe for comparison and it has been secluded like this since before the dinosaurs died out 80 million years ago this long-term isolation has allowed his animals to evolve completely separate from other continents and has cultivated Madagascar famous unique ecosystem with 80 to 90% of animal and plant life not being found anywhere else in the world Madagascar used to be part of the giant southern supercontinent Gondwana but broke away as part of the tectonic plate that makes up India and Pakistan this tectonic plate travelled north where it eventually crashed into Asia about 25 million years ago forming the Himalayas but when this plate was closer to Africa a landmass broke away creating Madagascar meaning that Madagascar is technically a little bit of Asia that just happens to be Africa's largest island the coast Madagascar used to be connected to Gondwana and has been in isolation for so long it was thought that the unique plants like strange bore about trees and some animals were ancient relics leftover from when it was part of Gondwana this is now known not to be the case and actually Madagascar's flora and fauna is mostly made up of descendants of animals there grated here and then colonized the islands over the past 40 million years or so so it's ecosystem is a mixture of different species that originated from all over the continents that border the Indian Ocean and that have had the chance to spread out and evolve in an insular environment Madagascar also has a very diverse climate for such a small land mass there are hot and humid winds battering the west side of the islands but that are halted at the country's Highlands this is maybe east side of the island into a hot and humid jungle but the west side dry and littered with deciduous trees and the south of the island is very dry with some parts even being considered deserts there are also environments that are completely unique to Madagascar like the spiny forests that are found on the southern tip the traveling animals that found themselves on Madagascar had many different habitats to evolve into so animals are very different from one area of the island to the other and is why Madagascar is sometimes referred to as the world's eighth continent not too long ago Madagascar also had its own megafauna distinct from the ones that could be found in other parts of the world by being an isolated environment Madagascar was protected from a lot of factors that led to the extinction of the megafauna in South America and the northern hemisphere one of these being humans which Madagascar didn't have until as recently as 1,500 years ago being one of the last places in the world to be inhabited by people this men that Madagascar's megafauna died out much more recently than in other parts of the world the largest animal that ever lived in Madagascar was the elephant bird it was a rat site which is the family that contains all the famous flightless birds like ostriches and emus although you might think that the elephant birds closest relative might have been an ostrich due to its large size and then they live in Africa a study on the DNA of elephant bird bones has found that their closest living relatives are actually the Kiwi which is not only a tiny bird but also 7,000 miles away the rat site family has many strange relationships like this making their evolutionary history quite puzzling however the popular theory is that ratites were mostly able to fly around 50 million years ago where they flew to these sparse and isolated islands they have been found on like New Guinea Australia New Zealand and Matt skaar it is thought that fifty million years ago one of these flying rat's ancestors landed in Madagascar where due to less competition they became giants being the islands main large herbivore filling a niche similar to an elk or a deer it is thought that these giant birds fed out on open plains and light forests and had not evolved for dense jungle living like a cassowary or some species of MOA but Madagascar had a different herbivore that was doing this job of prowling the jungles for food miniature hippos the Malagasy hippo was a tiny species of hippo that was probably quite similar in size to the pygmy hippo that is found in East Africa so opposite to the elephant birds the hippo shrank down significantly from their mainland relatives mr. Worf ISM might have been due to Madagascar being a smaller landmass meaning that the hippos weren't able to obtain as much food but it could have also been that the hippos didn't need to be as big because there were less large predators on the island and this would make a lot of sense because these hippos were much better adapted to walking and running on land than other hippos and probably spent a lot more of their time out of the water so it seems that use less competition in Madagascar these hippos took the land and started living a lot more like cows than hippos it isn't really understood how these hippos got there but they must have come over from Africa seeing as they are semi-aquatic it is possible that they may have swum over however long distance ocean swimming is not a behaviour seen in current hippos so it seems unlike they would be able to make a 250 mile trip in one go or what have even tried to it is possible that the island hopped across from Comoros which would have divided a journey up nicely although hippo remains would need to be found there to know for sure the alternative way they could have got across the ocean is that they may have made the trip during the Ice Age when sea levels were much lower narrowing the channel although there are less and fewer large carnivores in Madagascar than in Africa they are still here the largest being the Nile crocodile which is actually a very recent settler and likely only colonized the island after the extinction of another giant crocodile unique to Madagascar as little as 2,000 years ago it was called the voet and would have been around five metres long meaning if it was still alive it would have been among the largest interestingly it was a whole crocodile as well with two horns on the back of its skull however the largest terrestrial carnival in Madagascar is the fossa which despite its cat-like appearance is not related to felines and its closest non Madagascan relative are actually Mongoose this is because a small Mongoose like carnivorous mammal must have found its way to Madagascar about 25 million years ago when the island was closer to Africa with the lower amount of predators on the island the looser evolved to fill the niche of the apex predator meaning the fuzes are basically giant Mongoose this small prehistoric Mongoose like animal is also thought to be the ancestor of all of Madagascar's predatory mammals that belong to a family known as you Clara day because there weren't many predators on Madagascar this small mammal from Africa rapidly evolved to fill the ecological role that are filled by cats and dogs in other parts of the world the first son not only fills the same niche that a feline would fill in other parts of the world but has also convergently evolved with them it looks like a small mountain lion and has even of old retractable claws independently from felines as Mongoose do not have them these retractable claws were an adaptation that the fus are made to get better at climbing trees so they could hunt one of the most populous food sources in Madagascar lemurs the lemurs were one of the first animals to end up in Madagascar so it makes sense that when a predator also came to the island there would be one of the first animals to end up on the menu this was the same as with the recently extinct bird of prey known as the Malagasy crowned eagle some living birds like the Harrier Hawk sometimes hunt small lemurs but the Malagasy crowned eagle was much larger and it's possible that this was the bird Marco Polo was talking about and not the elephant bird this eagle was a descendant of the African crown eagle they came over to Madagascar and found an insular environment inhabited by monkey like animals so became a dedicated lemur killer the African crown Eagles hunt monkeys in Africa and lemurs probably needed very similar tactics to catch so the bird would have been right at home interestingly many large species of lemur that are too big to be eaten by any of Madagascar's currently living birds of prey still give out warning schools which is probably something they learnt to do when they were at risk of being hunted by the Malagasy crowned eagle and have just never lost this behavior lemurs have been in Madagascar for almost twice as long as the flu sir and his other family members with the most distantly related Madagascan lemur families diverging from each other about 40 to 50 million years ago giving a rough date for when they arrived lemurs are known as strepsirrhine primates which are primates are still having wet noses making them look a lot more like primitive primates than monkeys do the wet-nosed primates on most continents around the world like lorises or galagos are usually few in number and only occupy nocturnal niches with their habitats being dominated by monkeys so Madagascar has been a safe haven for these more primitive looking primates similar to a lot of other Madagascan animals the lemurs must have come over from a neighboring continent on a raft of leaves most likely Africa in the case of lemurs this can actually be better explained than with a lot of other animals that made the trip because some nocturnal lemur species like the mouse lemur are hetero thermic this means they are able to drastically reduce their metabolism and live off their fat reserves for some period of time if a lemur was stuck out at sea it would probably instinctly start to shut his body down and would be able to survive the journey until washing up in Madagascar the problem is that not all lemurs have this trait and the closest relative to lemurs lorises which are found in Asia do you not have it either so it is possible that being hetero thermic is something that a few lemur species have evolved to deal with the harsh climate on Madagascar and did not have it before arrival the diverse climate on Madagascar has massively influenced the evolution of lemurs to the point where their diversity arrivals that of all monkeys in the rest of the world combined also similar to the fiercer lemurs were colonizing an island that had low competition and therefore evolved to fill many niches that would be filled by non primates elsewhere lemurs like the aye-aye act similar to a woodpecker using their long finger to get it insects inside the trees and the smallest species of lemur is a third of the size of the smaller species of monkey meaning they occupy much smaller niches and up until fairly recently at least one extinct species of lemur would have eaten like a grazing hoofed mammal meghanadha Pez Megalodon s was a very unique lemur that probably lived a lot more like a koala or sloths very rarely leaving the trees and had a strange skull shape that was different from any living lemur or even primates his eyes were on the side of its head and it had a long howl like jaw based on its skull shape and the type of where found on its teeth it is thought the mega latias ate an almost exclusively leaf diet whereas most Lemus today eat mostly fruit seeds or insects Megan Oedipus was also a giant the largest lemur today is the Indri which can reach weights of ten kilos that Megalodon s was thought to be around fifty kilos and it wasn't the only giant lemur or even the largest there was the giant eye eye there was about five times the size of the living aye-aye and archaea lemur that had a body shape that showed it spent a lot of his time on the ground but was probably still well-suited for climbing it most likely lived like a boo boo the largest of all the giant lemurs was archaeon Duras there may have been only slightly smaller than a gorilla and had a body shaped like one too although a skull was quite different it had short hind limbs and relatively large four limbs meaning it probably walked along the ground like an ape so Madagascar being a safe haven for the wet-nosed primates saw them evolving in a similar way to the dry nose primates however giant ground sloths also walked a lot like Apes as well so it is probably more accurate to say that this is the way of walking commonly adopted by animals that have tree-dwelling ancestors just how lemurs are hunted by the future today a few thousand years ago Madagascar may have had a predator that was large enough to hunt the giant lemurs as well the giant fusa the giant fusa would have been around twice the size of the living fusa but was probably just as skilled of a tree climber it would have been a rapacious hunter of the various large lemur species on the island and would have been big enough to hunt juvenile giant Lima as well even though the giant fusa was fairly small compared to predators in the rest of the world being around the same size as a grey wolf it was the king of Madagascar's habitats being found all around the island but around 1,500 years ago this changed with the arrival of a new predator on the island humans but they did not travel the 250 from East Africa the first human settlers of Madagascar actually traveled three and a half thousand miles from Southeast Asia despite the incredibly long distance between Southeast Asia and Madagascar it has been thought that its original settlers had been Asian for a while and this is for a few reasons although the Malagasy language is distinct it borrows a lot from Asian languages like Malay or Japanese furthermore there is evidence that certain crops that originated in Asia like bananas and rice have been grown in Madagascar for a very long time however all this shows is that Southeast Asia has had a pretty big historical influence on Madagascar and this doesn't mean the original settlers of the island Wagin as all of these things could have been achieved through trade the findings in a study in 2012 has pushed this theory far beyond just speculation and now it is highly likely that the original settlers of Madagascar were from Southeast Asia more specifically the Malay Archipelago the study compared the DNA and the mitochondria of Malagasy people and Indonesian people mitochondria are cells that have descended from bacteria and now have a symbiotic relationship with animals this means they have their own DNA that can be studied independently from the DNA of the animal and in this case the human adding to this people can only inherit mitochondria from their mothers so the DNA can't be shuffled around by sex which means the changes in the DNA must be from random mutations which scientists are able to account for the study found that Malagasy and Indonesian DNA separated roughly around the time when archaeological evidence of humans first appeared in Madagascar it also found that the party of people that arrived would have been pretty small only containing around 30 women so how did they manage to get across the Indian Ocean why do they even try in the first place or was ending up in Madagascar an accident society in the Malay Archipelago was pretty advanced for the period when this happened specifically in boating technology so it was not out of the question that people from the region colonized Madagascar purposefully however there are reasons to doubt this one is that there is no evidence of later voyages to the island that you would think would have followed the first boat and a little bit like what happened when Europeans colonized the Americas also although there were many trade routes going from the Malay Archipelago to India and even as far as the Middle East there is little archaeological evidence of Austronesian people as far southwest as Madagascar so it would be strange if people were to just arrive there one day without previously visiting the area so it was likely an accident and this is very feasible seeing as there was a lot of trade to done with Indonesian sailors throughout the Indian Ocean so it would be unsurprising if a group of them may have been blown off course and ended up in Madagascar in fact the currents in the Indian Ocean traveled west would also push south when they passed India funneling a lot of the current towards Madagascar however this theory creates a bit of a mystery because if they were not intentionally colonizing Madagascar why were there any women aboard nevermind 30 as presumably the vast majority of sailing in 500 AD was done by men so this just adds to the mystery although the animals in Madagascar were definitely not helped by the arrival of humans they did not suffer as much as animals and other isolated islands like Mars in New Zealand or Dodos in Mauritius many of the megafauna species in Madagascar like elephant Birds giant fusa and mega latias may not have gone extinct until as little as six to seven hundred years ago meaning they cohabited the islands with humans for up to a thousand years in fact they went extinct so recently that their bones are often discovered on fossilized it's possible that the habitat destruction and overhunting were a big problem but many of the giant lemur populations were dwindling before the arrival of humans the for instance archaeon Duras may have been extinct for five hundred years before anyone set foot in Madagascar the diminishing lemur population show that there may mean other forces at play like climate change the giant lemurs may have died out there they shaped a lot of plant life on the island meaning in many cases you can still see the gap in the ecosystem that they used to occupy there are fruit trees that have seeds too big for any current lemur to swallow whole in order to spread them but largely my species like lemur were probably large enough to eat them which is why they evolved it is also possible that the reason for Madagascar's unique spiny forest ecosystems is because of giant lemurs once living in them almost all of the spine education that makes up the spiny forests found in the southern portion of the island belonged to a family of plants known as diddy rossi a this family of trees are found throughout africa but whereas the family members in mainland Africa are entirely thornless all of these trees in Madagascar have thorns the leaves on these trees are not really eaten by any lemurs that currently inhabit the island so what animals are these thorns defending the leaves from well there is a lot of evidence showing that recently extinct giant lemurs ate them and so the Madagascar variety of these plants needed to evolve to stop lemurs from eating too much similar to how certain lemurs give warning calls to a bird of prey that no longer exists these plants are protecting themselves from animals that are no longer alive the relationship between plants and animals on Madagascar was also very important in developing our understanding of how evolution works Charles Darwin was studying orchids that had been brought to him from Madagascar and he noted the extraordinary length of their nectaries one in particular had a flower spur measuring about 30 centimeters he predicted that there must be a moth at the had a proboscis long enough to reach down the plants throat to get to the nectar a few years later morgan sphinx moth was discovered that had a proboscis five times the length of his body and the subspecies of moth was named predictor in light of Darwin's prediction Madagascar may be a land of immigrants as his population is made up of a mixture of strange versions of animals that come from different parts of the Indian Ocean but it may be the ancestral home to some species as well Madagascar is home to half of all chameleon species and many scientists believe that this is where the creatures originated their fossil record is not very good and other theories put their place of origin in mainland Africa but it is possible that they evolved in Madagascar and then migrated out to colonize the rest of the world so Madagascar may be an island filled with evolutionary experiments showing how different animals could evolve while in isolation but also its unique ecosystem may have left a mark on many other parts of the world too thank you for watching if you want to watch more videos like this you can subscribe and a massive thank you goes to my patrons especially the big contributors like Sammy Vaz grim Marshall Green Falls and Brandon clop if you would like to support me as well then you can go to patreon you you

Channel: Moth Light Media

Views: 304,795

Rating: 4.9484105 out of 5

Keywords: Madagascar Biology, First Madagascans Asian, Asian Malagasy, Madagascar, Malagasy People, Animals, Lemur, Lemurs, Giant Lemurs, Evolution, Insular Evolution, Biology, Elephant Bird, Giant Fossa, Fossa, Paleontlogy, Island Ecosystems, Paleontology, Grey, Giant Eagle, Minature Hippos, Spiney Forest, Forest, Madagascar Climate, Archeondaris, Malagasy Hippo, Indian ocean, 500AD, Sailing, First Settlers of Madagascar, Africas Largest Island, Malagasy

Id: -DbqimrRtgs

Length: 20min 24sec (1224 seconds)

Published: Thu Mar 05 2020

Reddit Comments

[u/icticus2]

his channel is great

[u/MinimumFlatworm]

really nice! but is it possible that there was NO vicariance whatsoever? sure, it could’ve been mostly dispersion after the island isolated, but not a single species remained from Gondwana?