Things dinosaurs may have had or did

[CarnegieCollector]

I hesitate to label the use of venom as "evil". It's a mechanism developed for efficient prey capture that minimizes the risk of injury to the predator. I don't believe any adaptation that helps an animal survive should be labeled as "evil". That said, isn't there some suspicion that carnosaurs may have been venomous? The idea of venomous dinosaurs fascinates me, and anyway, there are venomous mammals too, so it's not like it can't be evolved amid a primarily nonvenomous lineage.

I honestly would be more surprised if dinosaurs did not form relationships outside their species, and could definitely see a Tyrannosaurus befriending a Triceratops, though I doubt that relationship would be beneficial for either party. I once saw a documentary in which a lone lioness had a habit of adopting orphaned antelopes, only being a lion, she couldn't really teach the antelope the skills it needed to survive, and moreover, while she was looking after the antelope, she would forego hunting, effectively starving herself, which made her weaker and less capable of defending her ward.

I think it would be more unusual if monogamy only developed in the avian lineage. I strongly suspect that non-avian theropods exhibited monogomy, at least in some species.

Inflatable sacs are also highly likely in my book. Basically, the way I see it is that, if birds have these features, at least some types of non-avian theropods probably did too. Maniraptoriform theropods have changed very little since the Cretaceous.

It's already known that iridescence was present in some non-avian dinosaurs. Analysis of the scleral rings of dinosaurs also seems to indicate nocturnality in some genera, though how reliable that analysis is is up for debate.

The others, I don't really know of any arguments either for or against them, so who knows?

Afraid that's very unlikely. It only works for frogs because of their skin and pitohui because of their oily feathers. That's also a might oversimplification, both poison and venom come in countless forms http://mentalfloss.com/article/67171/what-difference-between-venom-and-poison

I vaguely remember reading a book that mentioned a type of bird whose flesh seemed to be poisonous to some people. Nobody seemed to know what was causing people to become ill from it, because not everyone who ate it would experience the symptoms. I don't think they ever targeted the chemical cause, or the source of the toxin. I wish I could remember what kind of bird it was so I could look it up again. I believe it was some type of ground fowl though.

the reason I said it would seem more evil is because, for people, it considered evil to stand idly by and watch something die. It's considered remorseless and cruel. For animals, it's normal, for us, it would be considered evil 
That poor lion.....I can't imagine being her......using up all your time and effort to raise something that eats grass.
I just love iridescent anything, so I'm all over that! 
The poisonous fowl meat sounds annoyingly familiar to me as well. Just can't remember what it was, or where I read about it.

[The Atroxious]

the reason I said it would seem more evil is because, for people, it considered evil to stand idly by and watch something die. It's considered remorseless and cruel. For animals, it's normal, for us, it would be considered evil 
That poor lion.....I can't imagine being her......using up all your time and effort to raise something that eats grass.
I just love iridescent anything, so I'm all over that! 
The poisonous fowl meat sounds annoyingly familiar to me as well. Just can't remember what it was, or where I read about it.

Fair enough about the venom. The difference between human perspective and the perspective of the venomous animals in question is that humans evolved to be pack hunters, like lions or wolves, making it easier to take down large prey quickly. Komodo dragons, on the other hand, do not hunt in large packs, yet they hunt animals significantly larger and more powerful than themselves. They don't have any way of killing these animals quickly, so they do the next best thing, which is to bite first, then wait for the animal to succumb. Since carnosaurs typically preyed on sauropods, which were likewise much larger and more powerful than them, it fits with the speculation that they may have been venomous.

Also, I did some searching, and it seems that the poisonous bird in question was the quail. It's thought to be caused by the plants quails will eat during migration, though the exact plants in question remain a mystery. The condition, called coturnism, which causes the deterioration of muscle cells, does not occur in everyone, and there is a genetic factor suspected to be involved in individual sensitivity.

[Derek.McManus]

Interesting ideas...I suspect dinosaurs exhibited many of the traits of modern animals and possibly some we can only speculate about!

[Tyto_Theropod]

I have to nitpick on the venom idea - I believe that the consensus now is that komodo dragons aren't actually venomous. The 'symptoms' observed can be attributed to shock and blood loss. On the other end of the spectrum, though, it's interesting to consider dinosaurs taking up toxins from food which would become part of their system and make them less appetizing to potential predators. The hooded pitohui (https://en.wikipedia.org/wiki/Hooded_pitohui) does this, so maybe some of its distant ancestors did too? You never know...
Iridescent dinosaurs would certainly be cool - and of course it's not limited to scales, as there are plenty of birds with iridescent feathers (which are, after all, modified scales). Just think of how amazing a heavily feathered species like Caudipteryx would look with the colours of a peacock.

Venom is a lot better documented in Komodo dragons than typically presented, it's presence isn't just assumed through visible symptoms (which was however the case for the previous theory of symbiotic bacterial colonies used for hunting aid) but rather through glands in the lower jaw.


Pitohui are hardly alone, the ability to absorb toxins and use them for self defense is found everywhere from plants to vertebrates, and nudibranchs can even absorb the stinging cells of their prey (jellies) to use for defense.

Thank you for your input Star, your posts are always fascinating. In fact I was merely using the Hoded Pitohui as an example of an animal that did this, and at that one that is very closely related to dinosaurs - I realize now that I did not make that clear! AFAIK, the discovery of venom in komodo dragons is still being debated and I had put forward the 'against' argument. I stand corrected if I'm wrong there, though.

Oh, i didnt know about the Komodos venom thing. Still Intresting though. I'm 90% certain that carnivorous dinosaurs would have had the next best thing though: deadly bacteria build-up from eating flesh. Woulda probably of worked the same way as venom for the most part. Intresting idea about the toxins from food! That would make a lot of since!
A peacock-ish caudipteryx would be really cool! If I can remember right, scientists found that Oviraptor had a very flexible, short tail that maybe possessed long display feathers like a peafowl.

http://phenomena.nationalgeographic.com/2013/06/27/the-myth-of-the-komodo-dragons-dirty-mouth/

The only reliable model for the bacteria theory was the our old friend the Komodo dragon, and the venom theory has basically overtaken it, so it no longer has any real way of holding up. Even if the dragons aren't venomous, I still doubt they are deliberately exploiting bacteria.

Random: Don't butterflies also absorb chemicals from flowers to taste bitter and be poisonous?

Yes, an example being the well-known Monarch butterfly, which utilizes the poison in milkweeds, the foodplant of the caterpillar. This is the exception rather than the rule though and most species of butterfly are not poisonous.

I honestly would be more surprised if dinosaurs did not form relationships outside their species, and could definitely see a Tyrannosaurus befriending a Triceratops, though I doubt that relationship would be beneficial for either party. I once saw a documentary in which a lone lioness had a habit of adopting orphaned antelopes, only being a lion, she couldn't really teach the antelope the skills it needed to survive, and moreover, while she was looking after the antelope, she would forego hunting, effectively starving herself, which made her weaker and less capable of defending her ward.

The lioness was named Kamunyak and was observed in the Samburu National Reserve in Kenya. Interestingly, Mark Witton has made a piece of speculative art depicting a similar situation with Tyrannosaurus and Triceratops - the accompanying blogpost is a very interesting read and explains some the of spychology that might have been behind the lioness's behaviour: http://markwitton-com.blogspot.co.uk/2015/03/tyrannosaurus-and-triceratops-friends.html

Interesting ideas, though, DTF - keep 'em coming!

[tyrantqueen]

Oh, i didnt know about the Komodos venom thing. Still Intresting though. I'm 90% certain that carnivorous dinosaurs would have had the next best thing though: deadly bacteria build-up from eating flesh.

Lions and other carnivorous mammals today don't have this...I don't think a theropod would either. It wouldn't need it anyway, the prey would probably die from blood loss.

[Derek.McManus]

I suspect that they ambushed their prey with a massive bite and waited for blood loss to set in!

[CarnegieCollector]

Oh, i didnt know about the Komodos venom thing. Still Intresting though. I'm 90% certain that carnivorous dinosaurs would have had the next best thing though: deadly bacteria build-up from eating flesh.

Lions and other carnivorous mammals today don't have this...I don't think a theropod would either. It wouldn't need it anyway, the prey would probably die from blood loss.

e
They dont? That's strange. I coulda sworn that carnivores eat meat, it rots in their teeth, then when they bite something it infects that something from the bacteria. A theropod would not need it, as you said, but it just seems weird that they wouldn't have bacteria build up in their teeth.

[Tyto_Theropod]

Oh, i didnt know about the Komodos venom thing. Still Intresting though. I'm 90% certain that carnivorous dinosaurs would have had the next best thing though: deadly bacteria build-up from eating flesh.

Lions and other carnivorous mammals today don't have this...I don't think a theropod would either. It wouldn't need it anyway, the prey would probably die from blood loss.

e
They dont? That's strange. I coulda sworn that carnivores eat meat, it rots in their teeth, then when they bite something it infects that something from the bacteria. A theropod would not need it, as you said, but it just seems weird that they wouldn't have bacteria build up in their teeth.

No hard feelings, it's a common misconception. The thing is, nature rarely takes a belt-and-braces approach. So looking at some popular Theropods and the way their 'weaponry' is designed, something like a Giganotosaurus might well have taken huge bites out of its prey and then waited for the effects of blood loss to set in, while Tyrannosaurus had enough bite force to kill its prey outright if it was able to land a bite in the right place. The Dromaeosauridae might have got on top of the animal (which was probably a lot smaller than is often depicted in popular culture) and then used their talons to dispatch it. None of these would really have been any more effective with venom involved.

[tyrantqueen]

Oh, i didnt know about the Komodos venom thing. Still Intresting though. I'm 90% certain that carnivorous dinosaurs would have had the next best thing though: deadly bacteria build-up from eating flesh.

Lions and other carnivorous mammals today don't have this...I don't think a theropod would either. It wouldn't need it anyway, the prey would probably die from blood loss.

e
They dont? That's strange. I coulda sworn that carnivores eat meat, it rots in their teeth, then when they bite something it infects that something from the bacteria. A theropod would not need it, as you said, but it just seems weird that they wouldn't have bacteria build up in their teeth.

I've never ever heard that. There's just as much bacteria in the natural world that would do the job anyway.

[HD-man]

Parthenogenesis:

Here's hoping someone gets both of my awesome references.

Henry Wu: You're implying that a group composed entirely of female animals will...breed?
Dr. Ian Malcolm: Not at all, they could reproduce without breeding.
Henry Wu: What...a dinosaur reproducing asexually?
Dr. Ian Malcolm: It's called parthenogenesis!
Henry Wu: It's not a question of what its called! It's a simple question of hard evidence! No large reptile is known to reproduce asexually.
Dr. Ian Malcolm: Well, it doesn't matter. Life, uh...finds a way.

Iv always pictured tyrannosaurs and raptors being monogamous animals.

Ditto (See the Bakker quote), especially when it comes to eudromaeosaurs (See the Zelenitsky/Therrien & Mike quotes).

Quoting Bakker (See Raptor Red):

Three hours north of our Lakota quarries we have sites from the end of the Cretaceous, sixty-six million years ago, when that most famous of dinosaurs, T. rex, played the top predator role. The great tyrannosaurs are cousins of the raptors, and the tyrannosaur data matrix helps us look into the mind of the raptor. My colleague from the Black Hills Institute, Pete Larson, has discovered a remarkable thing about the gender roles in rex. The biggest, most powerfully muscled specimens are female, as shown by the structure of the bones around the base of the tail.
Female dominance is a powerful piece of evidence that permits us to reconstruct the private lives of Cretaceous predatory dinosaurs. A family structure built around a large female is rare in meat-eating reptiles and mammals today, but it's the rule for one category of predatory species — carnivorous birds. Owls, hawks, and eagles have societies organized around female dominance, and we can think of tyrannosaurs and raptors as giant, ground- running eagles.

Quoting Zelenitsky/Therrien (See "Taxonomic affinity" under "Discussion": http://onlinelibrary.wiley.com/doi/10.1111/j.1475-4983.2008.00815.x/full ):

Montanoolithus strongorum is only the second type of maniraptoran clutch known from North America, after that of Troodon formosus (Horner and Weishampel 1996; Varricchio et al. 1997, 1999). Our cladistic analysis reveals that TMP 2007.4.1 belongs to a maniraptoran theropod that is phylogenetically bracketed by Citipati (Oviraptoridae) and Troodon (Troodontidae) + Numida (Aves); the basal position of Deinonychus in this analysis may be due to missing data (50%) for this taxon. The phylogenetic position of Montanoolithus within Maniraptora indicates that this taxon is more derived than Oviraptoridae but less derived than Troodontidae. The only maniraptorans (besides Troodon) known from the Two Medicine and Oldman formations of North America are caenagnathids and dromaeosaurids (Weishampel et al. 2004), which represent the most probable egg-layers of Montanoolithus. However, the crownwards position of Montanoolithus relative to oviraptorids may support a dromaeosaurid affinity.

Quoting Mike ( http://blog.everythingdinosaur.co.uk/blog/_archives/2008/11/15/3977934.html ):

By studying the fossil the scientists have been able to determine that this dinosaur dug its nest in freshly deposited, loose sand, possibly along the shore of a river. An analysis of the substrate under the actual fossil indicates that the dinosaur disrupted the rock underneath, indicating that there was a substantial amount of effort put into the digging when excavating the nest. Perhaps this indicates that the mated pair worked together or that both the front claws and the strong hind limbs were used to construct the nesting mound.

[Gwangi]

I always imagined dromaeosaurus living more like modern game birds. A single male and several females. Kind of like chickens.

[HD-man]

I always imagined dromaeosaurus living more like modern game birds. A single male and several females. Kind of like chickens.

Why Dromaeosaurus specifically? In any case, I get where you're coming from. However, based on what we currently know, "giant, ground- running eagles" is a more accurate analogy.

[CarnegieCollector]

I always imagined dromaeosaurus living more like modern game birds. A single male and several females. Kind of like chickens.

That's an Intresting idea! I can kind of picture that. If I can remember right, JP3 had a pack of raptors that was 1 male and a bunch of females, or visa versa. Don't a lot of animals live like that? Or is it just birds?

[Gwangi]

I always imagined dromaeosaurus living more like modern game birds. A single male and several females. Kind of like chickens.

Why Dromaeosaurus specifically? In any case, I get where you're coming from. However, based on what we currently know, "giant, ground- running eagles" is a more accurate analogy.

Truthfully that's how I imagine a lot of the maniraptoriformes.

[Newt]

That's an Intresting idea! I can kind of picture that. If I can remember right, JP3 had a pack of raptors that was 1 male and a bunch of females, or visa versa. Don't a lot of animals live like that? Or is it just birds?

The "harem" structure is not terribly common. Species with this social structure naturally place great emphasis on male-male competition, often in the form of actual combat, as it's a sort of "winner-take-all" system where the strongest males get to breed with many females and the other males don't get to breed at all, or only through risky cuckoldry strategies. If any dinosaur species lived this way, we would expect to see males that were distinctly larger and/or better armed than females, just as we see in modern lions, chickens, wapiti, and elephant seals. But, larger size in males does not necessarily imply a harem structure, it only implies emphasis on male-male combat, which can also occur in animals with more gender-balanced social structures (hominid apes, cattle) or no real social structure (bears, snapping turtles, giant salamanders, stag beetles, etc.) ,

It is much more common in social (and, for that matter, non-social) animals for the sexes to be similar in size or the females somewhat larger. This does not necessarily imply female dominance, it's just reproductive logic (each egg/offspring is very expensive for a female, and a larger female can bear more or larger eggs/offspring, while each sperm is very cheap for a male and being larger does not have a significant effect on the male's ability to produce sufficient sperm).

[HD-man]

That's an Intresting idea! I can kind of picture that. If I can remember right, JP3 had a pack of raptors that was 1 male and a bunch of females, or visa versa. Don't a lot of animals live like that? Or is it just birds?

Actually, the JP3 raptor pack has a bunch of males & females. In fact, I'm not completely sure what kind of social structure they're supposed to have: On the 1 hand, they work together as a true pack w/a division of labor, etc.; On the other hand, they apparently nest colonially; This doesn't make sense b/c colonial nesters do work together ("Some species, like ospreys, learn of food sources from their flockmates in the colonies where they live": http://www.nytimes.com/1993/01/19/science/rabbits-beware-some-birds-of-prey-hunt-in-packs.html?pagewanted=all ), but not as a true pack. My best guess is that they're supposed to be a competition-based hierarchy of male-female pairs that work together to hunt & raise their young, presumably based on "the notions of "alpha wolf" and "alpha dog"" ( http://io9.gizmodo.com/why-everything-you-know-about-wolf-packs-is-wrong-502754629 ). In actuality, wolf packs are families. The same goes for extant dino packs ("Cooperative hunting is executed by pairs, family groups, or sibling groups, and is generally related to cooperative breeding": https://www.academia.edu/3513923/Possible_social_foraging_behavior_in_the_Red-backed_Hawk_Buteo_polyosoma_ ) & probably extinct dino packs.

Truthfully that's how I imagine a lot of the maniraptoriformes.

I asked b/c what you said reminded me of the Martin quote below. As you can see, Martin seemingly had the same idea as me (which makes sense given the aforementioned fossil nest evidence). To your credit, I wouldn't be surprised if at least of some of the more herbivorous theropods had a harem structure. However, to add to what Newt said, do any of the more carnivorous birds have a harem structure? Based on what we currently know, pair-bonding makes more sense for the more carnivorous theropods. Besides the aforementioned robust=female & fossil nest evidence, see the Bakker & Varricchio et al. quotes below for more hints of theropod pair-bonding.

Quoting Martin (See Dinosaurs Without Bones: Dinosaur Lives Revealed by their Trace Fossils):

On higher ground above the floodplain, a male–female pair of predatory theropods (Dromaeosaurus) paused from digging up small mammals from out of their burrows with their rear feet. They raised their heads, looking for whatever had provoked alarm calls from the birds and pterosaurs now passing overhead. Their footprints and excavations had disturbed a considerable amount of soil in the area. But they had much more to do before leaving. Once convinced the alarming behavior below had nothing to do with them, they went back to uncovering their furry morsels, sniffing the ground and scraping with their rear feet.

Quoting Bakker (See Raptor Red):

Fossil trackways of acros found in Texas show them hunting in pairs, trailing herds of multi-ton astrodons, and it's reasonable to suppose that these pairs represent mates working together. Since raptor brains were far larger for their body size than those of acros, we can surmise that the raptor society was more complex as well. I like to think that Utahraptor emotional ties between male and female, parent and young, were exceptionally strong and rich.

Quoting Varricchio et al. (See Nest and egg clutches of the dinosaur Troodon formosus and the evolution of avian reproductive traits):

The longer time required by coelurosaurians to generate a clutch with monoautochronic ovulation and brooding may have necessitated a longer pair-bond between mates and greater parental investment in coelurosaurians like Troodon in comparison with typical crocodilians.

[Newt]

Actually, the JP3 raptor pack has a bunch of males & females. In fact, I'm not completely sure what kind of social structure they're supposed to have: On the 1 hand, they work together as a true pack w/a division of labor, etc.; On the other hand, they apparently nest colonially; This doesn't make sense b/c colonial nesters do work together ("Some species, like ospreys, learn of food sources from their flockmates in the colonies where they live": http://www.nytimes.com/1993/01/19/science/rabbits-beware-some-birds-of-prey-hunt-in-packs.html?pagewanted=all ), but not as a true pack. My best guess is that they're supposed to be a competition-based hierarchy of male-female pairs that work together to hunt & raise their young, presumably based on "the notions of "alpha wolf" and "alpha dog"" ( http://io9.gizmodo.com/why-everything-you-know-about-wolf-packs-is-wrong-502754629 ). In actuality, wolf packs are families. The same goes for extant dino packs ("Cooperative hunting is executed by pairs, family groups, or sibling groups, and is generally related to cooperative breeding": https://www.academia.edu/3513923/Possible_social_foraging_behavior_in_the_Red-backed_Hawk_Buteo_polyosoma_ ) & probably extinct dino packs.

I think you're giving an awful lot of credit to the writers of JP3 to suppose they thought through any of this stuff...

[Balaur]

On the subject of venomous dinosaurs, na, they don't need it. I'm sure that extinct dinosaurs exhibited things like:
- Homosexual behaviour. A lot of birds are known to mate and be attracted to the same sex. Like a quarter of all black swan couplings are same sex, lots of gay penguins, and I even believe there are aome seabird colonies made up of almost entirely female-female couplings.
- Iridescent and bioluminescence: Iridescent scales is certainly a possibility, and we know for a fact that Microraptor had iridescent feathers. I'm a bit skeptical about bioluminescent abilities. The best analogues for dinosaurs are birds and crocodilians. I will say that some baby birds do have like little shiny things around their mouths so the parent can identify each chick and feed them. But since most dinosaurs were born precocial I don't think it was especially common.
- Sexual dimorphism: Dinosaurs certainly exhibited this. Though since the vast majority of crocodilians and birds, the males are larger than the females, only reversed in a few species (such as phalaropes)
- Unique Nesting Behaviour: Dinosaurs mainly nested on thr ground, likely building large mounds like crocodiles. What is very interesting is that at least one crocodilian, the Schneider's dwarf caiman, will nest next to termite mounds, and the movement of the termites would actuslly further incubate the eggs.

[Mickey Milkovich]

It would be quite interesting to live in the era of dinosaurs. http://bigessaywriter.com/blog/top-20-deadly-animals-everyone-should-avoid but dangerous at the same time. This article will help you to dive into the world of dinosaurs for some time.

[suspsy]

One of the things I really hated in the original WWD series was the female T. rex driving off the male shortly after they had mated. I think it's much more plausible that T. rex, and other theropods, largely practiced monogamy like most extant birds.

I would also love to see CollectA or Safari or any other company make a theropod figure with an inflated throat pouch. That concept is so beautiful to me.

When it comes to theropods hunting in packs, I think we need to keep in mind that a certain behaviour isn't necessarily shared by all members of the same family. Lions live in prides, but tigers, leopards, and jaguars don't. Grey wolves, dingos, and dholes live in packs, but maned wolves, foxes, and tanukis don't. And coyotes only form temporary packs for bringing down large prey. So even if say, Deinonychus was a pack hunter, it doesn't follow that Velociraptor and Dakotaraptor were.