50 million years of incredible shrinking theropod dinosaurs

Most of you who look at such things already know birds are thought to be direct descendants in the theropod lineage. This is one of the latest studies confirming what many of us have thought all along. When you watch large birds walk imagine them with a dino tail and teeth. Jurassic park with a little imagination.. They actually (several years ago) got a chicken embryo to grow a six segment boney tail... and in another report the bird actually had the beginning of teeth.. The old stereotype of slow and sluggish dino's was represented rather well IMO with the Jurassic Park movies and the Velociraptors scenes.. If we ever do develop a time machine where we could go back in time what a sight to behold....... providing we did not become dino poo before we could even open our eyes....

The results? As revealed by the title of the paper (and the title of this article), what has emerged is a robust and well-supported model showing a prolonged, directional trend in size reduction in the theropod lineage leading to birds: a trend that is continuous across 50 million years of theropod history, and which shows the animals at successive nodes becoming ever-smaller as we get closer to birds in the phylogeny

Because our results allow us to map the appearance dates of lineages onto the phylogeny, we can see that evolutionary rates across part of the lineage leading to birds occurred much faster than expected compared to the rest of the tree – up to four times faster, in fact (Lee et al. 2014a). This seemingly explains why several groups of tetanuran theropods – allosauroids, tyrannosauroids, compsognathids and others – appear near-simultaneously in the fossil record: it seems that the time intervals between their originations really were very short. Why evolution was occurring so rapidly in these animals remains, of course, an unknown.

www.scientificamerican.com...

they aren't shrinking they just aren't living long enough to grow large.

That's right! reptiles grow their whole life. I had a pet chameleon and he grew from 5 inches to 15 in six months of good feeding.

Now imagine if it lived for 900 (like Adam did) that chameleon would be the size of a Volkswagen Micro bus with a tail. It would not need it's clenching hands because it would be to big to climb trees so it would develop flat feet. It wold eat vegetation and animals. and if its tongue still worked it could catch a man from 25 feet away. In short it would look like a Triceratops.

Thank God they only live for 10-14 years or we would have some BIG problems. It was ok back then because mans populations were limited and these animals could live virtually without ever seeing a man.

a reply to: 727Sky

They actually (several years ago) got a chicken embryo to grow a six segment boney tail… and in another report the bird actually had the beginning of teeth..

Bingo.

I hold for the most part that "dinosaurs" (Terrible Lizards) were the same species as today. See 50 foot sharks, alligators and purposes.The earth was on a different axis, there was but one season of eternal summer and the fervent fauna generated way more O2 than it does now, making these species bigger and older.

So imagine a three hundred year old flightless bird standing 12 feet tall with fangs?

What a world that would be to see.

And the ground thundered.

originally posted by: 727Sky
The old stereotype of slow and sluggish dino's was represented rather well IMO with the Jurassic Park movies and the Velociraptors scenes.. /

At the time those films came out, the scientists were telling the film makers that velociraptors could run 60mph. Slow and sluggish? Maybe you're perceiving the limits of animatronic technology in 1993?

a reply to: ChesterJohn

Dinosaurs were not reptiles.

originally posted by: AugustusMasonicus
a reply to: ChesterJohn

Dinosaurs were not reptiles.

Indeed, something people often forget.

I think this study, as well as the recent study done which shows that feathers (or feather like coverings) were actually the norm for most (if not all) theropod (not the sauropods) dinosaurs shows that birds are dinosaurs.

One key thing to remember from the extinction event that "killed off" the dinosaurs is that no animal weighing over 25Kg survived, be it a mammal, reptile or dinosaur. It is highly probable, therefore, that the smallest dinosaurs survived as well and evolved into what we now know as birds. It is also worth noting that right after the extinction event 65 million ya, Giant meat-eating birds roamed the earth

I actually once tried to get a zoo to change the name of its "Bird House" to "Dinosaur House", but didn't try long enough to make the change. A good project for someone though.

originally posted by: centhwevir1979

originally posted by: 727Sky
The old stereotype of slow and sluggish dino's was represented rather well IMO with the Jurassic Park movies and the Velociraptors scenes.. /

At the time those films came out, the scientists were telling the film makers that velociraptors could run 60mph. Slow and sluggish? Maybe you're perceiving the limits of animatronic technology in 1993?

You are correct that did not come out the way I meant it to. The Velociraptors in the movies were anything but slow.

I have had friends with pet birds who were darn smart... So I can only imagine some of the theropods having the same or more intelligence than some of our current feathered friends.. 60 mph ? I had not heard that but some birds even today are quite fast and agile on their feet. The Ostrich can do a little over 40 MPH or close to 70 kph.. I have never heard how fast the terror bird could run but no doubt it was fast.. What a past this world has seen.

yeah, the dinosaurs didn't really go extinct. They likely underwent some severe genetic bottlenecking and began their transformation to our Thanksgiving and Christmas dinner.

Delicious, tasty dinosaurs.

a reply to: bigfatfurrytexan

Lol. If Ebola or any number of potential slatewipers have their way with us, it will be the slow circling of those same dinosaurs overhead looking down at the piles of dead tasty humans.


Soft and pink…. mmm.

originally posted by: ChesterJohn
they aren't shrinking they just aren't living long enough to grow large.

That's right! reptiles grow their whole life. I had a pet chameleon and he grew from 5 inches to 15 in six months of good feeding.

Now imagine if it lived for 900 (like Adam did) that chameleon would be the size of a Volkswagen Micro bus with a tail. It would not need it's clenching hands because it would be to big to climb trees so it would develop flat feet. It wold eat vegetation and animals. and if its tongue still worked it could catch a man from 25 feet away. In short it would look like a Triceratops.

Thank God they only live for 10-14 years or we would have some BIG problems. It was ok back then because mans populations were limited and these animals could live virtually without ever seeing a man.

LOL. I can't believe people still reference ridiculous Kent Hovind arguments as legitimate facts. Hopefully this was sarcastic because I don't think ANYBODY actually buys that nonsense anymore. At least I hope!

a reply to: Barcs It is true some reptiles continue to grow depending on their food intake throughout their lives..

Yep many Parrots live to be in their 80s but remain the basic same adult size unless they really get fat.. I have read or heard (?) that the oxygen content of the atmosphere was much higher during the Triassic and Jurassic periods of our history until the Carbon cycle got all kinds of messed up about 65 to 66 million years ago which killed off much of the ocean life and much of the Dino population.

The Oxygen-Rich Cretaceous Atmosphere


Analyses of the gases in these bubbles show that the Earth's atmosphere, 67 million years ago, contained nearly 35 percent oxygen compared to present levels of 21 percent. Results are based upon more than 300 analyses by USGS scientists of Cretaceous, Tertiary, and recent-age amber from 16 world sites.* The oldest amber in this study is about 130 million years old.

The higher oxygen content allow bigger bugs and bigger everything... Not to mention many of the Dinos had superior plumbing for breathing.
geology.com...

a reply to: intrptr

to the circle of life.

Using birds as a way to rid yourself of the recently deceased has been a long standing tradition in parts of the world that are rocky/mountainous.

a reply to: bigfatfurrytexan

I heard that too. Like in Tibet. Can't dig graves in solid rock. So they use carrion birds as their "undertakers".