Raz Science question: Why no tiny Dinosaurs?

[Razgovory]

Something I always wondered about when I was a kid.  How come there were no Dinosaurs the size of mice, or at least none found?  There were dinosaurs the size of chickens, but I was led to believe that was about as small as they got.  Certainly there were other animals that were tiny during the time period and it's hard to believe that tiny mammals, reptiles, and amphibians managed to out compete tiny Dinosaurs every time and every place for 100 million years.

[Tamas]

Where do you draw the scientific boundary between the skeleton of a reptile and a tiny dinosaur?

[Eddie Teach]

Because mouse-sized dinosaurs are just lizards.

[Darth Wagtaros]

They were all eaten.

Dinosaurs weren't lizards.

[Razgovory]

Where do you draw the scientific boundary between the skeleton of a reptile and a tiny dinosaur?

I don't know where to begin here.

[Razgovory]

Oh and to clarify, I mean Dinosaurs during the Triassic-Cretatious period.  Not later avians like Hummingbirds.

[Barrister]

Something I always wondered about when I was a kid.  How come there were no Dinosaurs the size of mice, or at least none found?  There were dinosaurs the size of chickens, but I was led to believe that was about as small as they got.  Certainly there were other animals that were tiny during the time period and it's hard to believe that tiny mammals, reptiles, and amphibians managed to out compete tiny Dinosaurs every time and every place for 100 million years.

A few moments of googling show that there are a few dinosaurs more the size of squirrels.

I give you Nemicolopterus.

http://dsc.discovery.com/news/2008/02/11/pterodactyl-dinosaur.html

[Grey Fox]

We call them Birds.

Damn it, you pre-empted me.

[Viking]

we don't have many fossils for small complex animals like this one, the size of a rat

http://en.wikipedia.org/wiki/Anchiornis_huxleyi

we don't have fossils for mammals and reptiles of that age and size either. This one is smaller than an adult rat but larger than an adult mouse. So small dinosaurs did exist.

[Brazen]

There's a tiny pterosaur (probably called Tony)  in this list that weighed just a few ounces.

http://dinosaurs.about.com/od/typesofdinosaurs/tp/Five-Smallest-Dinosaurs.htm

[Viking]

A few moments of googling show that there are a few dinosaurs more the size of squirrels.

I give you Nemicolopterus.

http://dsc.discovery.com/news/2008/02/11/pterodactyl-dinosaur.html

Pterodactyls (which are pterosaurs) are not dinosaurs, so no. But if you are uninformed idiot by choice like Raz this might not matter.

http://en.wikipedia.org/wiki/Pterosaur

Pterosaurs are often referred to in the popular media and by the general public as flying dinosaurs, but this is incorrect. The term "dinosaur" is properly restricted to a certain group of reptiles with a unique upright stance (clade Dinosauria, which includes birds), and therefore excludes the pterosaurs, as well as the various groups of extinct marine reptiles, such as ichthyosaurs, plesiosaurs, and mosasaurs.

[Viking]

There's a tiny pterosaur (probably called Tony)  in this list that weighed just a few ounces.

http://dinosaurs.about.com/od/typesofdinosaurs/tp/Five-Smallest-Dinosaurs.htm

Strange that a page named the 5 smallest dinosaurs has a list of 10 animals of which only 1,2,3,5 and 7 are actually dinosaurs. Nrs 8 and 9 are actually mammals and in no colloquial sense dinosaurs.

[HVC]

There's a tiny pterosaur (probably called Tony)  in this list that weighed just a few ounces.

http://dinosaurs.about.com/od/typesofdinosaurs/tp/Five-Smallest-Dinosaurs.htm

Strange that a page named the 5 smallest dinosaurs has a list of 10 animals of which only 1,2,3,5 and 7 are actually dinosaurs. Nrs 8 and 9 are actually mammals and in no colloquial sense dinosaurs.

"Here's a list of the 10 smallest prehistoric animals"

[Barrister]

There's a tiny pterosaur (probably called Tony)  in this list that weighed just a few ounces.

http://dinosaurs.about.com/od/typesofdinosaurs/tp/Five-Smallest-Dinosaurs.htm

Strange that a page named the 5 smallest dinosaurs has a list of 10 animals of which only 1,2,3,5 and 7 are actually dinosaurs. Nrs 8 and 9 are actually mammals and in no colloquial sense dinosaurs.

[Darth Wagtaros]