Welcome Guest [Log In] [Register]
Speculative biology is simultaneously a science and form of art in which one speculates on the possibilities of life and evolution. What could the world look like if dinosaurs had never gone extinct? What could alien lifeforms look like? What kinds of plants and animals might exist in the far future? These questions and more are tackled by speculative biologists, and the Speculative Evolution welcomes all relevant ideas, inquiries, and world-building projects alike. With a member base comprising users from across the world, our community is the largest and longest-running place of gathering for speculative biologists on the web.

While unregistered users are able to browse the forum on a basic level, registering an account provides additional forum access not visible to guests as well as the ability to join in discussions and contribute yourself! Registration is free and instantaneous.

Join our community today!

Username:   Password:
Locked Topic
Polar Tyrannosaurid Feathering; It makes no sense
Topic Started: Jul 30 2017, 07:19 PM (1,424 Views)
YixianBirdBeast
Adolescent
 *  *  *  *  *
Why would a Tyrannosaurid from a northern environment suddenly go back to being feathered when all of it's closest relatives were fully covered in scaly skin? if Tyrannosaurus was completely covered in scaly skin then something like Nanuqsaurus should be covered in scaly skin instead of feathers too
Offline Profile Goto Top
 
kusanagi
Adolescent
 *  *  *  *  *
Most theropods were not extensively feathered. Tyrannosaurs are not an exception. And if they were not insulated by feathers in frigid climates they must have used other means like subcutaneous fat.
Edited by kusanagi, Jul 30 2017, 07:52 PM.
Offline Profile Goto Top
 
Ebervalius
Member Avatar
Transhuman
 *  *  *  *  *  *  *  *
1- this does not go in Science Central
2-the information on Tyrannosaurine tegumentation we have is by no means conclusive, but since Nanuqsaurus was not only a polar animal, but also a dwarf by Tyrannosaurid standards, I would not be surprised if it turned out to have feathers.
The Sirens of the Land of Fire
Codex Ebervaliorum

Spoiler: click to toggle
Offline Profile Goto Top
 
DroidSyber
Member Avatar
I'll cut ya swear on me mum
 *  *  *  *  *  *
YixianBirdBeast
Jul 30 2017, 07:19 PM
Why would a Tyrannosaurid from a northern environment suddenly go back to being feathered when all of it's closest relatives were fully covered in scaly skin? if Tyrannosaurus was completely covered in scaly skin then something like Nanuqsaurus should be covered in scaly skin instead of feathers too
1. How is it in any way proven that tyrannosaurids were fully scaled? We have scale imprints from warm-climate animals, and mostly from areas that we have evidence of scaly skin on feathered animals. Feathers are also the ancesteral trait to tyrannosaurids, and so it makes no sense to just assume that since we have some scale impressions from tail and leg that now we will assume that all tyrannosaurids were predominantly scaly, no matter the size or climate.

2. Last I checked, Science Central is for sharing new scientific discoveries and research, and discussing them. This is you sharing your personal opinion inspired by a single scientific paper that shows, in the most controversial interpretation, that an elephant-sized active carnivore living in a climate mostly similar to Louisiana had lost all of it's downy covering. What you have posted is neither scientifically accurate based on current understanding, nor is it correct to be placed here. It would be much more appropriate in General discussion then here.

3. . The lifestyle, size, and climate Tyrannosaurus inhabited made something like complete featherlessness at least semi-logical. Nanuqsaurus was around the size of a polar bear, living in a climate at it's warmest similar to Ontario/ New York State in terms of tempature, and was probably cooler. The only reason I can see for an animal to loose it's insulated covering is for heat radiation, not in the slightest something Nanuqsaurus needed.
Non Enim Cadunt!

No idea how to actually hold down a project.
Offline Profile Goto Top
 
Hybrid
Member Avatar
May Specula Grant you Bountiful Spec!

Phasianidae

If I sound rude while critiquing, I apologize in hindsight!
"To those like the misguided; look at the story of Man, and come to your senses! It is not the destination, but the trip that matters. What you do today influences tomorrow, not the other way around. Love Today, and seize All Tomorrows!" - Nemo Ramjet
ノ( ͡° ͜ʖ ͡°)ヽ

Posted Image
Offline Profile Goto Top
 
LittleLazyLass
Member Avatar
Proud quilt in a bag

Integument coverings wouldn't be constant across a family - just look at elephants and mammoths, or humans and chimps. Something like Tyrannosaurus reducing its feather covering significantly? Makes perfect sense, it was gigantic and lived in a fairly hot ecosystem. Somewhat smaller creatures in colder environments, like a Gorgosaurus? Probably a bit fuffier than that. Nanuqsaurus, the smallest tyrannosaurid and the one that lived in the coldest environment? I'd expect it to be primarily fuzzy.

No, I'm not gonna justify this by trying.
totally not British, b-baka!
Posted Image You like me (Unlike)
I don't even really like this song that much but the title is pretty relatable sometimes, I guess.
Me
What, you want me to tell you what these mean?
Read First
Words Maybe
Offline Profile Goto Top
 
IIGSY
Member Avatar
A huntsman spider that wastes time on the internet because it has nothing better to do
 *  *  *  *  *  *  *  *  *
I feel the need to point out that just because T.rex wasn't fluffy doesn't mean it didn't have feathers. Elephants aren't fuzzy, but they have a thin coat of hair. Tyrannosaurus would probably have a thin coat of feathers.
Posted Image
Projects
Punga: A terraformed world with no vertebrates
Last one crawling: The last arthropod

ARTH-6810: A world without vertebrates (It's ded, but you can still read I guess)

Potential ideas-
Swamp world: A world covered in lakes, with the largest being caspian sized.
Nematozoic: After a mass extinction of ultimate proportions, a single species of nematode is the only surviving animal.
Tri-devonian: A devonian like ecosystem with holocene species on three different continents.

Quotes


Phylogeny of the arthropods and some related groups


In honor of the greatest clade of all time


More pictures


Other cool things


All African countries can fit into Brazil
Offline Profile Goto Top
 
LittleLazyLass
Member Avatar
Proud quilt in a bag

Quote:
 
2. Last I checked, Science Central is for sharing new scientific discoveries and research, and discussing them. This is you sharing your personal opinion inspired by a single scientific paper that shows, in the most controversial interpretation, that an elephant-sized active carnivore living in a climate mostly similar to Louisiana had lost all of it's downy covering. What you have posted is neither scientifically accurate based on current understanding, nor is it correct to be placed here. It would be much more appropriate in General discussion then here.

To my understanding Science Central isn't actually restricted to new stuff, it's just that's all people use it for. I tried making a palaeontology general thread once (or dinosaurs general? Not sure) but it didn't catch on.

Quote:
 
The only reason I can see for an animal to loose it's insulated covering is for heat radiation, not in the slightest something Nanuqsaurus needed.

Well, there's a variety of factors at play. Heat radiation is part of it, which can come down to climate (see elephants and mammoths) or other aspects of the ecosystem (like it being shaded vs open to the sun; see Sumatran rhinos compared to other species), as well as obviously size (see all the obviously hairy antelope). There's also lifestyle - ostriches have reduced leg integument to run, hippos and fully aquatic mammals have no fur, and naked molerat skin is a whole other bag of worms. Our own species lost our hair for reasons that as far as I would guess relate to sweating, which comes down to both lifestyle and climate. If we assume Kulindadromeus fuzz was homologous to theropod fuzz, then even basal, small, forest dwelling ceratopsians like Psittacosaurus became predominantly scaly for some reason or another. Just saying "big thing hot weather lose feathers" is really selling the complexity of integument selection short.
totally not British, b-baka!
Posted Image You like me (Unlike)
I don't even really like this song that much but the title is pretty relatable sometimes, I guess.
Me
What, you want me to tell you what these mean?
Read First
Words Maybe
Offline Profile Goto Top
 
HangingThief
Member Avatar
ghoulish
 *  *  *  *  *  *  *
Yixian, are you by any chance trolling us? Someone who claims to know you from another site said you're a troll, and this thread is pretty incriminating.
Hey.


Online Profile Goto Top
 
kusanagi
Adolescent
 *  *  *  *  *
Insect Illuminati Get Shrekt
Jul 30 2017, 08:20 PM
I feel the need to point out that just because T.rex wasn't fluffy doesn't mean it didn't have feathers. Elephants aren't fuzzy, but they have a thin coat of hair. Tyrannosaurus would probably have a thin coat of feathers.
Posted Image
All land mammals have hair and its possible the reason they are never lost is because its primary function is not insulatory at all but tactile, helping to detect ectoparasites, for example. On the other hand elephant hair though sparse is thermoregularory: it helps them cool down believe it or not.

To my knowledge the hairless parts of theropods and ornithipods do not display micro-hairs like human or elephant skin. Perhaps coats of mammal hair were exapted from smal, scattered tactile precedents of a sort widely seen throughout the animal kindgom whereas that of dinosaurs and pterosaurs came from dermal display filaments? The latter fits the ornithischian evidence and to some degree maybe the theropod evidence but I don't see any pterosaur evidence. What pterosaur hair/plumage is known is insulatory whereas that of cerapods and heterodontosaurs is not.

Hairlessness in mammals is not well understood. People who followed the aquatic ape theory and criticism thereof will have acquired a notion that hairless mammals other than man himself are either aquatic, large mud wallowers or fossorial. Besides man himself as an outlier each of these generalisations is a bit problematic: an aardvark or a warthog is very different in its degree of fossoriality from a naked mole rat and so might hardly be comparable. Another pig called the babirusa includes both naked forms and the hairiest wild pigs of all within the same kind of habitat and climate. And so on. The underbellies of Pan and Gorilla show hairlessness in a tropical forest climate so hominins primitively inhabited a degree of nudeness. Some ethnohistorical hunter gatherers in Tasmania and Fuego walked around in the cold without clothing although unlike other cold climate mammals they did have fire. And finally other than dorsal and display feathers the ostrich is almost featherless if you care to look at its thighs or behind its wings. It is very hard to generalise from these cases of various mammals and one ratite why hair or feathers are lost on land. All cold climate mammals and presumably dinosaurs are however naturally insulated unless they can rely on technology.
Edited by kusanagi, Jul 31 2017, 09:21 AM.
Offline Profile Goto Top
 
LittleLazyLass
Member Avatar
Proud quilt in a bag

Quote:
 
To my knowledge the hairless parts of theropods and ornithipods do not display micro-hairs like human or elephant skin.
It's hard to say; we know feathers and presumably other dinosaur filaments can coexist on the same part of the body as scales, and we also know that feathers do not preserve as easily as scales, particularly in the sort of three-dimensional preservation that tyrannosaur, ceratopsid, and ornithopod scale impressions come from. So having those kinds of small filaments is indeed possible.
totally not British, b-baka!
Posted Image You like me (Unlike)
I don't even really like this song that much but the title is pretty relatable sometimes, I guess.
Me
What, you want me to tell you what these mean?
Read First
Words Maybe
Offline Profile Goto Top
 
kusanagi
Adolescent
 *  *  *  *  *
Little
Jul 31 2017, 10:23 AM
Quote:
 
To my knowledge the hairless parts of theropods and ornithipods do not display micro-hairs like human or elephant skin.
It's hard to say; we know feathers and presumably other dinosaur filaments can coexist on the same part of the body as scales, and we also know that feathers do not preserve as easily as scales, particularly in the sort of three-dimensional preservation that tyrannosaur, ceratopsid, and ornithopod scale impressions come from. So having those kinds of small filaments is indeed possible.
But although there are birds with feathered feet, scaly bird feet do not have small, tactile feathers. My argument from this is that while feathers and hair are analogous when they exist in pelts, only mammal hair has a secondary function that feathers lack. Is it relevant that mammal skin is more complex overall than that of reptiles, birds included?

Against this is the tactile facial whiskering of kiwis with possible whisker pits sometimes recognised in Mesozoic dinosaurs and even notosuchians. Feathers may then have a tactile function but never do they form an equivalent of human, elephant or mole rat body hair in the partial absence of a pelt. Instead the suppressed feathers become reticulae of bird feet.
Edited by kusanagi, Jul 31 2017, 11:03 AM.
Offline Profile Goto Top
 
Ebervalius
Member Avatar
Transhuman
 *  *  *  *  *  *  *  *
HangingThief
Jul 30 2017, 10:29 PM
Yixian, are you by any chance trolling us? Someone who claims to know you from another site said you're a troll, and this thread is pretty incriminating.
Why is it incriminating?
The Sirens of the Land of Fire
Codex Ebervaliorum

Spoiler: click to toggle
Offline Profile Goto Top
 
HangingThief
Member Avatar
ghoulish
 *  *  *  *  *  *  *
Ebervalius
Jul 31 2017, 12:10 PM
HangingThief
Jul 30 2017, 10:29 PM
Yixian, are you by any chance trolling us? Someone who claims to know you from another site said you're a troll, and this thread is pretty incriminating.
Why is it incriminating?
The fact that he created a thread with an incredibly uninformed statement about a topic that's known to cause vicious arguments incriminates him as a troll to me. Especially since this is the same statement that got him told off by several people when he worded it much more rudely in another thread.
Hey.


Online Profile Goto Top
 
LittleLazyLass
Member Avatar
Proud quilt in a bag

An uninformed statement and returning to a topic he got a three-day ban for does necessarily show somebody is a troll as opposed to, being nice, them not being very bright. It is something trolls will do, but on its own cannot be considered evidence.
totally not British, b-baka!
Posted Image You like me (Unlike)
I don't even really like this song that much but the title is pretty relatable sometimes, I guess.
Me
What, you want me to tell you what these mean?
Read First
Words Maybe
Offline Profile Goto Top
 
1 user reading this topic (1 Guest and 0 Anonymous)
ZetaBoards - Free Forum Hosting
Free Forums. Reliable service with over 8 years of experience.
Go to Next Page
« Previous Topic · Science Central · Next Topic »
Locked Topic