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42 votes
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Did neanderthals need vitamin C from the diet?

Humans can't synthesize vitamin C due to a dysfunctional enzyme L-gulonolactone oxidase, or "GULO". From Wikipedia: Loss of GULO activity in the primate order occurred about 63 million ...
Bryan Krause's user avatar
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13 votes
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How is the first Triceratops born?

Yes, there are many early examples of ceratopsians before Triceratops. The oldest clear member of the lineage is Liaoceratops: "the oldest ceratopsian ever found ... was about the size of a large dog. ...
iayork's user avatar
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10 votes
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Did birds descend from a single or multiple species of dinosaur?

The answer is "one common ancestor", but I'll expand. All organisms descend from one common ancestor so that question is not quite well-posed, but what you are actually asking I think is whether ...
Oosaka's user avatar
  • 3,253
10 votes

Is the Lucy fossil really what scientists claim it is?

Per the comments, the actual paper seems pretty like a pretty straightforward operation of normal science: Somebody noticed something that looked off about one of the bones and decided they'd look ...
jakebeal's user avatar
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8 votes

Can you identify this fossil?

It's a sea urchin (Echinoidea). It looks like a specimen of Lovenia or another genus from the heart urchin (Spatangoida) family. What you see is just the shell without the spines. Lovenia woodsii ...
adjan's user avatar
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8 votes
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Were there any vertebrates with 6 or more limbs?

I've not read it but this SE question Why don't mammals have more than 4 limbs? though not a duplicate (it asks about mammals not all vertebrates) may have some elements in its answers pertinent to ...
Pelinore's user avatar
  • 811
7 votes

Were there any flying dinosaurs?

Asides from flight-capable modern birds and their early ancestors1, there are several other therapod dinosaurs which palaeontologists suspect were capable of flight, "but in a manner ...
brazofuerte's user avatar
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7 votes

How could this fossil's soft tissue be preserved so well?

You're right that the authors don't comment on how they think the fossilization occurred. Since that process isn't the point of their article, my guess is that any discussion of it would have ...
Forest's user avatar
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6 votes
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Has the most recent common ancestor of all living birds lived after dinosaur mass extinction?

I suppose that by the mass extinction, you are referring to the Cretaceous–Paleogene extinction event that happened 66 mya. The Most Recent Common Ancestor (MRCA) ...
Remi.b's user avatar
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6 votes
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How can soft tissue exist in dinosaur fossils?

keratin and collagen are an incredibly tough molecules so if it is isolated from the environment (oxygen and bacteria) it could easily survive for that long. Not all proteins are equal some are very ...
John's user avatar
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6 votes

Why are mammals the only animals with pinnae / outer ears?

Short answer Mammalian hearing is unique and amazing. The mammalian ear is unique and highly sensitive with a built in amplification system that means even minute changes in sound can be detected. ...
John's user avatar
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6 votes
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What is the creature on the cover of the fourth edition of 'Dinosaurs: A Concise Natural History'?

It appears to be of the family Scansoriopterygidae. This dead-end family in evolutionary terms, thrived in woodlands at some point between 153 and 165 million years ago. They ranged in size between ...
Jiminy Cricket.'s user avatar
5 votes
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Were there any marine/aquatic dinosaurs?

There are a couple of specimens of a dinosaur species named Liaoningosaurus paradoxus that have been found with fish in their stomachs and skeletal features suggesting it was at least semi-aquatic. ...
wanderweeer's user avatar
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5 votes

Can a second mass extinction by microbes happen?

First of all, let’s consider your Methanosarcina scenario in specific. Methanosarcina with those properties are still around. So, there is no reason to expect that introducing some ancient ...
Wrzlprmft's user avatar
  • 585
4 votes

The Perplexing Trilobite: What is the Evidence Supporting The Hypothesis That They are Not Crustaceans?

Trilobites had bodies divided into 3 lobes lengthwise. Hence the name trilobite = 3-lobed critter. The head or cephalon of the trilobite is large, nearly as broad as the body and marked by sutures. ...
Draco Freon's user avatar
4 votes

When did birds and mammals diverge?

The Most Recent Common Ancestor (MRCA) of birds and mammals was the first amniotes. Fossil record The latest known fossil of amniotes are 312 million years old (Bentou and Donoghue, 2007). Genetic ...
Remi.b's user avatar
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4 votes
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When did birds and mammals diverge?

You can check it easily in the timetree website: http://www.timetree.org/ Put a mammalian species as taxon 1 (Homo sapiens) and a bird as taxon2 (Gallus gallus) in the first pair of boxes and hit run....
biojl's user avatar
  • 354
4 votes

How can paleontologists identify morphologically different fossils as members of the same species?

Radically different body shapes and sizes represent overall phenotype. Overall phenotype was used briefly in the 1960s and 1970s for species identification under a statistical distance method called "...
Karl Kjer's user avatar
  • 7,693
4 votes

Have skeletons of "failed" animals been found yet?

Short answer The dodo and Irish Elk, both going extinct relatively recently, are examples of species that have yielded skeletons and went extinct, at least partly, due to maladaptations. Background ...
AliceD's user avatar
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4 votes
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What is this row of pits along the "upper lip" of theropod skulls?

They are called Nutrient Foramen which are innervation of blood vessels and nerves, you see the same thing in reptile and bird skulls (mammals tent to pack it all into one or two large openings). They ...
John's user avatar
  • 14.8k
4 votes

Is there a way tell apart dinosaurs from similar extinct reptiles?

There are several defining morphological characteristics of dinosaurs. Including their ankle structure and perforated acetabulum, Aka the hole in their hip goes all the way through, as well as a few ...
John's user avatar
  • 14.8k
4 votes
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What were the three dinosaur evolutions and do they imply that bipedalism could have evolved multiple times in hominins?

"Dinosaur", when used properly, refers to a clade. There's no way for a clade to evolve multiple times, or even to really evolve at all as something that happens; it's just a name for a ...
Bryan Krause's user avatar
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4 votes
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Why Laramidia is more rich in dinosaurs than Appalachia?

Its not, there are just more trees over Appalachia. its easier to find fossil in dry climates which have more exposed bedrock and sedimentary rock. We find plenty of fossils in Appalachia just mostly ...
John's user avatar
  • 14.8k
4 votes
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Why is Archosauria a subclass and not a class?

See Bryan Krause's comment, but I'll add that the reason is historical. Linnaeus identified three classes of tetrapods (mammals, birds, and reptiles/amphibians), and reptiles and amphibians were later ...
Eonema's user avatar
  • 878
3 votes

How could this fossil's soft tissue be preserved so well?

Three major factors. the organism itself was small and thin enough to not be exposed as it decomposed, combined with the extremely fine grained nature of the matrix (rock) means the organism was held ...
John's user avatar
  • 14.8k
3 votes

Ethics in Paleontology

It depends entirely on where the fossils were dug up. In the US fossils on private land belong to whomever owns the mineral rights to the land, that landowner can do with the fossils as they will. On ...
John's user avatar
  • 14.8k
3 votes

Did insects and arachnids diverge before or after moving to land?

Those are two very separate questions. Arachnids include terrestrial groups such as spiders, scorpions, and other arthropods. Arachnids are members of Chelicerata, which includes horseshoe crabs, Sea ...
Karl Kjer's user avatar
  • 7,693
3 votes

Is there really a clear distinction between dinosaurs and birds?

The placement of the bird clade within the dinosaur clade is based on much more than just "having feathers and being warm-blooded"; paleontologists have discovered many, many ancient bird and theropod ...
Oosaka's user avatar
  • 3,253

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