Birds are dinosaurs!

[Albino Pterosaur]

Hello fossil collectors!I love both aquascaping(modern aquaria like planted tanks;biotopes;reef;frag;fish only tanks) and prehistoric wildlife.Despite birds are dinosaurs for some reasons;on internet;people who didn't know zoology and science ;birds are classified as theyre own clade!I started a war because of this on youtube and facebook posts about evolution of course

Why people classify them as a different type of animals?!Birds are dinosaurs because of feathers;skeletal structures;the same body plan?Comment your own thoughs!But ordinary people also grind my nerves because of ideas like this:Pterodactyls are flying dinosaurs while small rodents of the era were lizards !Oh my god!

[Troodon]

Welcome to the forum, agree birds are dinosaur see this post

http://www.thefossilforum.com/index.php?/topic/59137-ascending-process-evolution-revealed-birds-are-dinosaurs/

[Auspex]

Avian Theropods were a type of dinosaur, and birds are a type of Avian Theropod. In the big picture, this means that birds are dinosaurs, according to our ideas about evolutionary relationships and our system of classification. That they are derived from a lineage of dinosaurs is, at this point in our understanding, indisputable.

By the way, we do not have 'wars' here.

[LordTrilobite]

A fun fact is that birds actually do not have a defining feature that distinguishes them from non-avian Theropods. Pretty much every feature that we would describe as being a typical bird feature is present in Theropods. From asymmetric feathers to pygostyles and paedomorphic skulls. So there is no "line" when dinosaurs became birds basically.

[Auspex]

A fun fact is that birds actually do not have a defining feature that distinguishes them from non-avian Theropods. Pretty much every feature that we would describe as being a typical bird feature is present in Theropods. From asymmetric feathers to pygostyles and paedomorphic skulls. So there is no "line" when dinosaurs became birds basically.

The degree of centralization of mass is greater in Aves, though this is arguably an adaptation for flight (which persists in secondarily flightless species). Also, the skeletal clearance for eggs to pass through the oviduct is proportionally greater in Aves.

[dadrummond]

A fun fact is that birds actually do not have a defining feature that distinguishes them from non-avian Theropods. Pretty much every feature that we would describe as being a typical bird feature is present in Theropods. From asymmetric feathers to pygostyles and paedomorphic skulls. So there is no "line" when dinosaurs became birds basically.

Fun; not a fact. Theropods had mineralized teeth. Birds do not; they have beaks. This has been traced to a set of gene inactivations roughly 100 million years ago in the common ancestor of all modern birds (see this 2014 paper). This does not mean there was a "line," of course.

From that paper's introduction:

The absence of teeth or edentulism has evolved on multiple occasions within vertebrates, including birds, turtles, and a few groups of mammals (anteaters, baleen whales, and pangolins). There are also mammals with enamelless teeth (aardvarks, sloths, and armadillos). All toothless/enamelless vertebrates are descended from ancestors with enamel-capped teeth. In the case of birds, it is theropod dinosaurs. Instead of teeth, modern birds use a horny beak (rhamphotheca) and part of their digestive tract (muscular gizzard) to grind up and process food. The fossil record of early birds is fragmentary, and it is unclear whether tooth loss evolved in the common ancestor of all modern birds or convergently in two or more independent lineages.

[jpc]

A fun fact is that birds actually do not have a defining feature that distinguishes them from non-avian Theropods. Pretty much every feature that we would describe as being a typical bird feature is present in Theropods. From asymmetric feathers to pygostyles and paedomorphic skulls. So there is no "line" when dinosaurs became birds basically.

fused tarsometatarsals? Do any dinos have this feature? Do the most primitive birds lack it?

Point is... the line separating the two groups is subtle. Just like the reptile/mammals divide. Evolution is so cool.

Welcome aboard albino pterosaur

Edited November 28, 2015 by jpc

[Auspex]

fused tarsometatarsals? Do any dinos have this feature? Do the most primitive birds lack it?

There are two distinct lineages of Aves, discriminated in part by whether the fusing was proximate-to-distal, or distal-to-proximal.

My thinking is that these two groups evolved independently from different stock. Put that in your pipe and smoke it!

[jpc]

There are two distinct lineages of Aves, discriminated in part by whether the fusing was proximate-to-distal, or distal-to-proximal.

My thinking is that these two groups evolved independently from different stock. Put that in your pipe and smoke it!

Enantiornithines and 'regular birds'. My pipe is full.