A Dinosaur with a Beak and Feathers Unearthed in China | Hacker News Reader

A Dinosaur with a Beak and Feathers Unearthed in China

nytimes.com

94 pointsMrJagil39 comments

> "It was not a bird, but a dinosaur that was a close relative of birds."

I know it would lead to confusion in the article, but birds are classified as dinosaurs. However, there are many groups of dinosaurs and each classified by their evolutionary traits. Birds just happen to be the only group that survived to the present day. If dinosaurs are a superset of many species, birds would be a subset of them.

The interesting aspect is they found one that had evolved just enough to have a beak, but retained many of the characteristics of more primitive dinosaurs. Many dinosaurs not considered birds also had feathers, so that's not overly significant alone.

That said, countries like New Zealand had birds that went down a pretty similar evolutionary path that lived up until 700 or so years ago[1]. New Zealand is a pretty interesting place evolution wise. It answers the question of how birds would evolve if not exposed to any other major mammalian predators for centuries.

[1] https://en.wikipedia.org/wiki/Moa

Many dinosaurs also did not had feathers, some had scales, some had skin closet to mammals, and at least some were likeky warm blooded.

Birds are only part of a single branch of the tree of dinosaurs, and currently it's more than likely that most dinosaurs did not had feathers and are not really related to birds in any particular manner.

If you had citations for any of that, I would love to read it. Birds have been scientifically classified as dinosaurs for at least the past 20 or so years[1] and many (obviously not modern ones) lived in parallel to other dinosaur species in the late Cretaceous Period.

[1] https://en.wikipedia.org/wiki/Avialae

All birds are dinosaurs not all dinosaurs are birds, birds evolved from Theropods, there are other orders and suborders which were an evolutionary deadened and had nothing to do with birds.

https://en.m.wikipedia.org/wiki/Theropoda

From my first comment:

> "If dinosaurs are a superset of many species, birds would be a subset of them."

Birds are a subset of many species of dinosaurs but from one specific subgroup I wasn't contradicting you but some people think that all dinosaurs had feathers and are related to birds that is not the case.

The feather thing was also known considerably earlier than people think as early as Darwin people published books about birds being related to some dinosaurs since we had very early feathered and winged fossils.

Ah okay. Wasn't sure what you were leading to in your previous comments. I'm in agreement with you after your clarifications though :)

While we're clarifying nomenclature, I'd like to point out that "primitive" is to be avoided, as it may imply that a trait is simpler, inferior, or less adaptive, perpetuating the "ladder of progress" misconception of evolution.

"Ancestral" is preferred and should always be applied to traits rather than taxa, e.g., "Tongtianlong limosus retained many ancestral characteristics of older dinosaurs"

Good point. I didn't think about that aspect. I'm only an amateur biologist, so didn't consider the wording.

Ironically, I would consider a beak more primitive until the engineer in me screams teeth could be a sign of over engineering--not that I would personally give up my good (but high maintenance) teeth for a beak. Could probably write a entire book on "evolutionarily traits and trends for engineers."

Absolutely-it's important to consider the selective environment that a trait evolved in and evaluate all possible tradeoffs. You can see this in certain fishes where pharyngeal jaws permit eating hard prey (new food source!) but also increase the processing time for soft prey (bad if you're competing against critters that eat faster). Beaks are good for some reasons and teeth for others.

You may enjoy "principles of animal locomotion" - it's pretty engineering focused.

Sure, but that does not contradict the statement in the article, right? Some dinosaurs are birds, but this one was not.

Correct, but the language throughout article would likely lead a reader to assume birds are not part of the dinosaur family, since it's never implied that birds are dinosaurs either. Pesky implicits can be a pain in more than just programming sometimes.

It does state "Oviraptorosaurs are not direct ancestors of birds, but share a common theropod dinosaur ancestor with the lineage that later evolved to birds."

I wonder how this resurrection project is coming along http://www.theepochtimes.com/n3/1113874-the-frightening-disc...

Also, would anyone have any good theories as to why dinosaurs evolved feathers? and from what did it evolve from? was it hair?

I believe feathers evolved from scales. I think they were first beneficial for dinosaurs for their likely elaborate courtship/mating rituals if birds are any indicator of how other dinosaurs found mates.

Early feathers weren't useful for flying, keeping warm or making a creature look bigger, so I would figure the advantage that made them useful was related to mating.

The moa foot just looks like what you'd imagine a dinosaur foot to look like, doesn't it?

https://upload.wikimedia.org/wikipedia/commons/9/90/Moa_foot...

I assumed beak evolution was a flight adaptation to reduce weight. Teeth+jaws enable chewing which is much more effective at extracting energy and nutrients from food.

Birds have a lot of weight adaptations. Digestion is quick-and-dirty in order to minimize the time food must be carried around during digestion. Legs are generally very thin and break easily (one leg broken is very common) in order to save weight. Even feathers participate -- most of the surface area of the wing is constructed from feathers rather than flesh in order to save weight.

A Moa, for example, is similar-sized but has no teeth because it evolved from lighter birds. Why would a large dinosaur evolve a beak and lose the efficiency of teeth?

Here is an article [1] in the Mail Online which appears to give a possible explanation for beaks on dinosaurs. From the article, I can't quite figure out how they reached that conclusion. But it is at least a possible explanation.

[1] http://www.dailymail.co.uk/sciencetech/article-2517009/Myste...

Triceratops had a beak! It was for carving out pieces of fronds/palms etc. Bakker suggests that flowering plants invented beaked dinosaurs.

> "Bakker suggests that flowering plants invented beaked dinosaurs."

I'd say it's quite possible that it's at least one of the factors. Hummingbirds became experts at reaching nectar in flowering plants and in turn, many flowers such as trumpet plants evolved down a path that invests heavily in hummingbirds visiting them.

I have seen some clever orioles circumvent the process of nectar in exchange for pollen by snipping a hole in the bottom of a trumpet plant flower and drinking the nectar it wouldn't be able to reach otherwise.

> "Why would a large dinosaur evolve a beak and lose the efficiency of teeth?"

That's a good question. I'm just an amateur, but I can guess at a few reasons.

1) Diet was not hampered by having either beak or teeth and a beak requires less maintenance (no tooth decay) and energy to grow. Beaks can also be more equipped to open seed shells and other barriers to food than teeth. I'm always quite amazed at the way finches are able to pop the seed out of a tiny thistle seed at a rapid pace.

2) Birds use their beak and legs as "radiators" to help regulate their internal temperature[1]. May have helped this species to better adapt to its area than others.

[1] http://www.audubon.org/news/how-birds-keep-their-cool

Not paywalled: http://earthsky.org/earth/chinas-new-feathered-mud-dragon-di...

I guess this is a little tangental, but I've always liked these artist’s renderings.

Hand-drawn flora and fauna illustrations are definitely not appreciated enough these days! One of my favourites is John Lewin: https://en.wikipedia.org/wiki/John_Lewin And though most people are probably familiar, the Voynich Manuscript is also very beautiful.

And of course Kunstformen der Natur [1]. Even if Haeckel did cheat a bit.

[1]: https://en.wikipedia.org/wiki/Kunstformen_der_Natur

Wonderful!

> Tongtianlong limosus — the name means “muddy dragon on the road to heaven”

Did they name it after how they discovered it died? Ha.

Imagine if species were given posthumous names based on how they were wiped out...

Would Dodos would be "Eaten by sailors on a lonely island"?

> Would Dodos would be "Eaten by sailors on a lonely island"?

That is precisely where the name came from; i.e. the accretions left behind by satiated sailors after feasting on the endangered birds. The Great Vowel Shift hides its etymological roots.

The vowel shift[1] finished around the time the Dodo was discovered[2], so that's a fun story but it's wrong.

[1] https://en.wikipedia.org/wiki/Great_Vowel_Shift

[2] https://en.wikipedia.org/wiki/Dodo

It's also worth pointing out that the vowel sound of "oo" was basically the first vowel to shift in the Great Vowel Shift. So the spelling "doodoo" would have had its modern pronunciation as far back as the first claimed mention (an unsubstantiated claim in 1630s that the Portuguese found it in 1507), let alone when it was first credibly discovered (by the Dutch in 1598) or first mentioned in English (1628).

Interestingly enough, the Wikipedia page also suggests that the birds weren't found to be particularly appetizing.

I think it was a joke.

Perhaps... to cover my rear-end, I intentionally avoided assuming an intent and worded my post to comment only on the story itself.

Well played!

> Did they name it after how they discovered it died? Ha.

Actually, yes! From the original manuscript:

Tongtian, Chinese Pinyin, refers to Tongtianyan of Ganzhou, the first grotto south of the Yangtze River. Tongtian also means the road to heaven, a fitting epitaph for a deceased dinosaur preserved with outstretched arms. Long, Chinese Pinyin for dragon. Limosus, Latin for muddy, refers to the holotype specimen being found in an unusual posture in a mudstone.

> Long, Chinese Pinyin for dragon

It seems worth pointing out that long 龍 / 龙 is the word for a Chinese dragon, but konglong 恐龙 (character-by-character, "terrible dragon") is the word for "dinosaur".

  An artist’s rendering depicts 
  the oviraptorosaur, flailing 
  while mired in mud.

So... uh... why is it... such a, um... why is this dinosaur so clumsy and tragic?

Is it supposed to be the Napoleon Dynamite of dinosaurs?

Reminds me very much of the Cassowarys I saw in Australia. https://en.m.wikipedia.org/wiki/Cassowary

what's next, eye-stalks?

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