So that fringe pterosaur blog (oddly enough, that is not a link to David Peters) is offering $500 for a credible scientist to preform a phylogenetic evidence that supports his pet theory. How legal and/or acceptable is being a hired-gun phylogeneticist who comes up with evidence supporting unlikely hypotheses for money?
In related news, I may have discovered the way to be an evil phylogeneticist, which is a career option that I had neither considered nor thought possible.
It’s literally antiscience. Science means doing everything you can to prove your hypothesis wrong and be left with it as the only viable option. Cherry picking evidence to prove your hypothesis right is pseudoscience by definition.
Anonymous asked: Why is there such little variation among big dinosaur predators in comparison to big mammal predators? Big sabre-tooth cats, omnivorous bears, pack hunting dogs; Fuzzy Yutyrranus and scaly Carnotaurus couldn't be further apart in the family tree, but there is relatively little difference between the two; two digitigrade legs, big head, long tail, reduced forelimbs, etc. Why is this?
This is an interesting question that I had to think about for a bit. It’s certainly worth mentioning that the theropod bauplan is obviously very successful- Save for a long tail, it’s remained generally unchanged for some 240 MA. That said, there’s a lot more variety in large theropod predators than there appears to be at first glance: Megalosauroids such as Baryonyx and Torvosaurus have long arms with hooked claws, as do megaraptorans (whatever they may be). Abelisaurs are adapted for sprinting and swallowing; they have long legs with huge muscle attachments. Tyrannosaurs have massive skulls with bone-crushing teeth and pinched metatarsal bones for shock-absorbing. Carnosaurs seem to have been sauropod specialists; their skulls are strong when striking like a hatchet, rather than twisting side-to-side like tyrannosaurs.
Digitigrade legs are good for running fast, a useful skill for predators. Therizinosaurs were least digitigrade theropds, and they were mainly herbivores (most plants don’t do too much running). Bigger heads are longer levers for applying more force. Long tails help keep balance and allow you to turn more quickly. And not all large predatory theropods had short arms. I would say that the similarities in the general body shapes of carnosaurs, megalosaurs, .abelisaurs and tyrannosaurs are due to evolving from similar Generic Small Theropods™ and evolving to fill a similar nice as big-game apex predators
Another thing to consider is that stem birds in general, unlike fast growing mammals and birds, seem to have occupied several ecological niches during their lifetimes. So we tend to find more diversity of body shapes and sizes within species rather than between species.
revereche asked: I see a lot of feathered dinosaur art where the snout is left bare as a beak would be, but would that really be the case in dinosaurs that didn't have beaks?
As far as I can tell it’s because deinonychosaur specimens with preserved feathers seem to have bald snout-tips.
Not all though, Anchiornis and Eoenantiornis, for example, have feathers to nearly the tip of the snout. There must have been a lot of variation between species and clades when it comes to extent of feathering on the face.
An asker (who asked to remain anonymous) wanted a good explanation for why birds are considered dinosaurs. As I was tediously typing my usual answer on my tablet, it occurred to me that it would probably be a good idea to make a sort of masterpost addressing the various arguments people who accept evolution but aren’t familiar with cladistics tend to use when claiming birds aren’t dinosaurs. I want to be as thorough as possible so suggestions would be helpful.
We switched to a new classification system that requires groups to be monophyletic and abandoned ranks like Class and Order. Not really any particular scientific reason as much as a bookkeeping one. As much as proponents of birds=dinosaurs (including myself of course) hate to admit it, the difference between “birds evolved from dinosaurs” and “birds are dinosaurs” is mostly semantic. The one bonus is it allows you to see the lineage as a continuous acquisition of shared features, which is true either way, just with an arbitrary cutoff in the. “Evolved from” version.