Humans evolved from animals that can glide

[David George]

When we spread our digits we see a very small patch of skin between our digits.The same feature is very well seen in bats.flying squirrels and flying lemurs,etc.Does this not show that humans ancestors might have evolved from tree dwelling organisms.

[Invader Zim]

If that patch of skin wasn’t there between our "Digits" then we wouldn’t be able to open our fingers too well because that patch of skin allows you to spread your fingers easily. And, it also allows us to swim better with our hands as "Oars".

[Beetle]

As I know only bats have skin between their phalanges. Others such as squirrels just have between front and hind legs. And no it does not show that we evolved from any of those groups. Neither from aquatic forms like Lutra (otter I think) or beaver although thay also have swiming skin between their phalanges.

[Khaiy]

It must be a coincidence, as bats evolved to fly, not glide. I’ve never seen a morphology of skin between the digits that would allow for gliding rather than flight, and no human forerunner could fly. It’s much more reasonable to think along beetle’s and zim’s lines.

[David George]

That cannot be true the ancestors of monkeys might be tree dwelling animals like the ancestors of bats.the flying squirrel example was to tell that tree dwelling mammals evolved to flying squirrels,bats,small monkeys,etc.

[AstusAleator]

You’re falling into the trap of homologous and analogous structures. Just because echidnas have spines, doesn’t mean they evolved from porcupines. Similarly, just because dolphins have dorsal fins, doesn’t mean they evolved from Tuna.
Some humans have genetic anomalies that cause their feet or hands to be webbed. That demonstrates that our genome has the capacity to cause that to happen, but not necessarily that we at one time had an ancestor with webbed feet and or hands.
I don’t want to discourage you from scientific inquiry, but perhaps next time you have a hypothesis, you can do a little research before posting.

[Beetle]

quote David George:

That cannot be true the ancestors of monkeys might be tree dwelling animals like the ancestors of bats.

Speaking of bats does anyone knows what animals were the ancestors of them? And when did thay evolved and become true (todays) bats? I never thoght about it.

[AstusAleator]

That’s still a pretty big mystery. The fossil record doesn’t really have much information on that point. In fact, the evolution of flight as a whole is still quite a mystery.
There are different hypotheses:

1. They were arboreal gliders that evolved powered flight
2. They were terrestrial and used a patagium for intimidation and escape.
3. They evolved independently from a flying proto-mammal

we really don’t know though. So if you’re looking for something to dedicate your life’s research to, there you go!

[David George]

Hey AustusAleator I did not put on this topic before any research did you know evolutionary studies says that bats are more related to humans than to rodents.
For your question Beetle Bats are supposed to be divide from genus purgatorios which lived about 65 million years ago this is the genus from which even humans evolved but a very long after the evolution of bats.Bats were considered to be close relatives of flying lemurs but genetical studies deny this fact it is said bats and flying lemurs must have evolved from the same ancestor.If you want to know more I might help you.Little epauletted bat does have a face like a flying lemur or even a rat.

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[alextemplet]

Amazing. I never thought of that but there definitely does seem to be a family resemblance.

[AstusAleator]

Bats have incredibly diverse pheonotypes and karyotypes. There are bats with faces very similar to canids (flying fox) and those with faces more resembling mice (vespertilionids). The shape and appearance of their face is mostly just convergence. A detailed study of their skulls will reveal many differences.
Interestingly, most bats have the same teeth as insectivores (shrews, voles, moles, etc).

David I’d like to see some documentation on the relationship between lemurs and bats. Could you post that? There is a very large taxonomic gap between bats and lemurs (Chiroptera and Primate). I get the feeling that people may say their related just because of the convergent petagium, so could you please post a link to your source?

[David George]

Astus the flying lemur is not a lemur it has its seperate order Dermoptera."Colugo" is the original Malaysian word for the animal. Although it is also called a "Malayan flying lemur," it is not a lemur and it does not fly – but it is found in Malaysia.It merely glides on the wind currents rather than flying like a bat or a bird. The shocking fact is that it is also found in Rwanda and Burundi in Africa but no web page that I saw says it lives in Rwanda and Burundi.I got this information from the Encarta.There are two species that are extinct and two which are living[I have no idea if the one found in Africa are of a different species] in South East Asia.Bats evolved from the genus purgatorios and lemurs also evolved from this genus but a much later stage all primates have evolved from this genus but I think Tarsiers were the first primates to evolve.The reason why we see so mant differences between bats and primates is because bats evolved about 65 million years but primates evolved in a later stage.And another interesting fact the first primates evolved were nocturnal creatures with large eyes it was only in a later stage primates evolved into a diurnal creatures.Imagine humans having huge eyes and are nocturnal. 😆 .I will get you more information Astus if you give me a little more time.The picture in your screen is a flying lemur.

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[AstusAleator]

Thank you David. How embarassing, you’re right the flying lemurs are dermoptera. I should have remembered that, as I took mammology just a few weeks ago 😳 .
Flying lemurs are interesting, as are sugar gliders and flying squirrels. But do they really show a transitional morphology? What would it take to evolve from a glider to a flyer? The fact that there are several extant species of gliders, across several orders, but only one extant order of flying mammals, indicates to me that that transition is very difficult, rare, and imporobable.
Anyhow, the fossil record is still sadly lacking in transitional fossils for the evolution of flight. Archaeopteryx is the closest one that I know of, and it didn’t fly.
I think it’s really interesting that flight evolved independently in pterodactyls and was lost to their lineage when they went extinct. For me that kind of puts flight into perspective, as a biological characteristic rather than a fanciful idea. Flight was around long before birds or bats evolved, and WAY before humans. I think humans have a very romanticized view of flight (at least I do) and as a result, may look at the evolution of flight through that same lense.
I think that the lack of transitional fossils is an indication that the evolution from non-flying to flying occured very rapidly (relatively). I’ve heard of studies that supposedly showed that the alteration of one gene could account for the transition in petagium structure to allow flight, but I don’t really buy that. If that were the case, we’d have multiple extant lineages of flying mammals.

[alextemplet]

Just out of curiosity, does anyone know anything about the evolution of flight in insects? They were the first lifeforms to evolve flight, weren’t they? There’s also countless insect lineages to study, though I’m not sure how common enough insect fossils are to make serious investigation worthwhile.

[David George]

Astus as I told you before bats evolved from genus Purgatorius at about 65 million years.After few million years in the Paleocene epoch Plesiadapiformes evolved. This genus is the ancestor of the rodents along their side the flying lemurs evolved[They had their own genus].The bats evolved a patagium not to glide but to fly in the earlier times to provide lift.The first formed bats were the megabats which donot use echolocation to find food.They evolved larger wings to fly and for balance.Genus Petrolemuridae evolved during the paleocene epoch but only after the evolution of flying lemurs.This genus consists of animals resembling lemurs.It divided into genus Adapidae and genus Omomyidae.Adapidae consists of lemurs and lorises while omomyidae consists of tarsiers only here the cranial size of primates started to rapidly evolve.Any further doubts Please ask.

Alex my Friend there are lot of theories for the evolution of flight of Insects the order Plecoptera has many members that tell us about the evolution of flight in insects.The first formed members of this genus were only insects dwelling in water they started to move faster in water and at one point they started to skim in the water with only four legs then with two legs gradually developing flight as they found water provide more resistance than air.

[Beetle]

Thank you for the reply about bats David. Interesting. Are you trying to say that higher primates evolved from Tarsiers?

I didnt get this about Plecoptera and insect flight. Can you explain it little more. Are you saying that they evolved flight under water and that wings derived from legs?

[David George]

Yes Beetle higher primates evolved from tarsiers but not lorises and lemurs.Plecoptera have the ability to skim on water.Modern stoneflies walk on the surface of water, and raise their rudimentary wings if they feel a puff of air. They then get propelled across the water by the breeze .The ancestors of stone flies didnot have wings they skimmed on water with the whole body.Later they skimmed on water with four legs then with two legs by this time they could fly for short distances if there was a breeze eventually evolving to fly.The wings themselves are by many thought to be highly modified (tracheal) gills. And there is no doubt that the tracheal gills of the mayfly nymph in many species looks like wings.Wings were not derived fron legs.

[Beetle]

I have read about several theories. The one I was refering to when said that wings are derived from leg is "leg exsite theory". It also looks probable to me. But haven`t Plecoptera appeared later, after the Odonatas and Ephemeroptera? So we should be looking for first wing insects among them, I think Ephemeroptera ancestors.

[David George]

Great news Beetle I forgot about the evolution about insects.Did you know Plecoptera,Odonatas,Ephemeroptera[Mayflies] all belong to a mainly aquatic taxa.And ephemeropterais supposed to be the first evolved flying insect order.The first stage of the life of a mayfly is the nymph (larva), which not only looks very different from the adult, but lives in the water. When the nymphs hatch from the eggs, they are less than 1 mm long. They have no gills at first, and their body shape varies according to habitat.In older nymphs, gills are found in pairs on each segment of the abdomen (see pictures below). The gills extend from the sides of the body and are oval-shaped. These gills beat to control the flow of water through the body, which also controls the amount of oxygen and salt that flows through the body. Nymphs in still waters generally have larger gills, and those in running water have smaller gills; this allows the nymphs of each habitat to get their optimum flow of water. Not only do the gills function in uptake of water, salt, and oxygen, but they also send water off at right angles to the body. This is used to mislead predators. If the water simply flowed out the back of the nymph’s body, predators would know that the nymph was sitting at the beginning of the stream.This is where the gills evolved to wings remember may flies nymphs need water.Hope that is good enough.

[Georgie]

quote AstusAleator:

You’re falling into the trap of homologous and analogous structures. Just because echidnas have spines, doesn’t mean they evolved from porcupines. Similarly, just because dolphins have dorsal fins, doesn’t mean they evolved from Tuna.
Some humans have genetic anomalies that cause their feet or hands to be webbed. That demonstrates that our genome has the capacity to cause that to happen, but not necessarily that we at one time had an ancestor with webbed feet and or hands.
I don’t want to discourage you from scientific inquiry, but perhaps next time you have a hypothesis, you can do a little research before posting.

Sorry if i am butting into the discussion, i just wondered, aren’t most modern animals related if you follow their ancestory back far enough? It’s just a thought. For example, taking the echidna idea: Echidna and porcupines are both mammals, so if you followe their ancestory back far enough then might they have a comman ancestor?

[David George]

Offcourse you are right Georgie but we were telling about the closest relative.

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