Infinity Blade Regarding the "nomen protectum/nomen oblitum" exception in the code, it seems that if we were to apply the same strict standards to T. rex as we do with everything else, it actually wouldn’t apply here:
dinogoss.blogspot.com/2010/09/what-is-nomen-oblitum-not-what-you.htmlBut of course we don’t, so everything is just collectively fine with bending the rules a little if it means we can keep the name
Tyrannosaurus rex.
In pretty much every other case, it is a binding, non-negotiable rule that oldest valid name takes precedence, even if it has fallen out of use in the mean time and another name is much more popular (e.g. usage of the name
Allosaurus was also pretty much discontinued in the early 20th century in favour of "Antrodemus", and only really started being used again after Madsen published his 1976 osteological monograph, still the valid genus name is
Allosaurus).
T. rex, of course, is above the rules (even rules like this one, that already look like they were custom-made in its favour, but that it still somehow isn’t required to follow).
It doesn’t seem that obvious, or else I wouldn’t be unsure what exactly you mean by "the obvious". That we are mammals ourselves? Or that the majority of large, "charismatic" animals that are still extant are mammals, leading to them being perceived as the dominant animals today?
I also wouldn’t say that all humans have a general bias towards mammals, although many certainly do (likely due to being able to relate to mammals more than to animals less familiar to them, which perhaps, on top of that, they have been incorrectly told are "inferior" to mammals for most of their life, I would guess). There are also quite a lot of people who have the opposite, and are generally more into reptiles and/or birds, precisely because they are more different from ourselves and thus have more "exotic" and also less well-researched features than mammals.
The mandrill is one of the rare ocurrences of a mammal showing blue colours.
That blue is so rare is because blue pigments are extremely rare, and not found in the animals we are talking about (with mammals basically only having two kinds of pigments, eumelanin and pheomelanins, which give various shades brownish reds and yellows as well as darker browns and blacks), leaving blue to usually be achieved through structural color (i.e. not pigments, that selectively absorb some wave lengths of light, but through the use of microstructur that reflect and scatter light in such a way as so selectively interfere with some wave lengths, resulting in the complementary color of those wavelengths being perceived).
That is how a lot of birds, reptiles and insects can have blue coloration without the need for actual blue pigments, and that, in turn, enables them to also have green coloration, that comes about as a mixture of blue structural color and yellow (i.e. pheomelanin) pigments. That is also the way mammals can have blue eyes, and the way the facial skin of the mandrill achieves its blue coloration. That mechanism of structural coloration is also why a lot of blue or blueish black birds will appear iridescent, because the microstructure has a slightly different effect on the color depending on the angle of the light, which leads to the characteristic iridescence.
The problem for mammals is that structural colours require suitable structures to carry them, and something about the flexibility and the microstructure of hair just isn’t suitable to display them, so while mammals can (in rare cases) have blues on their skin, and they obviously can have blue irises in their eyes, they can’t evolve blue (and, by extension, green) fur. Which likely also has an effect on the ocurrence of blue skin, as a skin that is hidden below fur and thus can’t be seen anyway doesn’t have much of an evolutionary incentive to evolve flashy colors.
Most mammals are dichromats (some are even monochromats), so while they aren’t entirely color-blind for the most part, they don’t see color the same way we do, having just two kinds of colour detectors in their retinas, instead of our three or most other vertebrates’ four (which means they see colour as a spectrum between two different primary colors rather than three or four, and as you will know from art class, you can’t make all the colors we are familiar with by mixing just two primary colors).
Which in turn means there is less of a selective pressure to evolve different pigmentations (or the ability to display structural colors), because other mammals won’t see them anyway (which is likely why birds also have a more diverse range of pigments than mammals, in addition to structural color in their feathers). This is the result of something called the "nocturnal bottleneck", which is related to the first 150 Ma of mammalian evolution having been spent as small and predominantly nocturnal animals living "in the shadow of the dinosaurs".
For a nocturnal animal, color vision is much less important (because cones are less light-sensitive than rods), and thus got lost or reduced from the ancestral vertebrate condition (which is tetrachromacy, as found in birds). There are however exceptions, mammals with decent colour vision (albeit not as good as most other vertebrates) such as ourselves and other primates, which evolved trichromacy as an adaptation for feeding on fruit (where good color-vision comes in very handy to find colorful, ripe fruit from between green foliage). And that is likely why some of the most colorful mammals, including the Mandrill, are found among those primates; their conspecifics can see those colors, meaning they are useful for display (unlike in, say a cat or an ungulate, for which it matters little whether they are green or brown, because both look the same to them).
Whatever you have heard is a massive exaggeration. Nobody ever had to make a new unit of measurement for any bite force, ever. The implausibility of this is quickly understood when you consider that there are many forces in the universe that are greater or smaller than any bite force ever to an almost inconceivable extend, and that the units for those forces already exist. Any force is measured in some derivative of newtons. If you see it reported in some other unit, then it is probably not a force (I am somewhat known for regularly going on rants whenever someone comes along thinking that "psi" is a unit of force, which it is not), or, at best, a force being translated into a unit of mass (like kilograms or tons) for illustrative purposes (which works because given we stay on earth, there is a direct relationship between a mass and the force it is equivalent to through its gravitational attraction to the planet below).
Dunkleosteus’ bite back when it was first estimated (Anderson and Westneat 2007) was considered to be among the highest bite forces known, and the highest of any fish. However, notably that was before there had been any published estimate for great white shark and
O. megalodon bite forces, which positively blew
Dunkleosteus out of the water a year later, and also before most other published estimates for truly enormous bite forces, such as those for giant theropods (though there were some estimates for
T. rex, notably Meers 2002 and Erickson et al. 1996, which were indeed higher than the forces estimated for
Dunkleosteus), pliosaurs, whales and large crocodilians. So there simply weren’t that many other things to challenge it back then, and because science journalists and other sloppy people on the internet often fail to do their homework, and just take anything they see written somewhere at face value without considering the context, many people still like to claim
Dunkleosteus had a record-breaking bite force.
The original estimate for
Dunkleosteus was around 4.4 kN (anterior) to 5.4 kN (posterior) for a large individual, which is not weak by any means, but not particularly awe-inspiring either (by comparison, a record-sized 3.3 ton great white shark was later estimated to have a bite force of about 18 kN for a posterior bite by Wroe et al. 2008). A later paper by the same authors (2009) revised that upwards to 6 and 7.4 kN respectively.
In the papers they talk about "large individuals" which they variously estimate at 6 to 10 m, however it is notable that based on most recent estimates those same "large individuals" were likely quite a bit smaller, closer to 4 m (see Engelmann 2023ab), so that makes the bite forces a lot more impressive for the size of the fish than they initially were.
Nevertheless, there are a lot of animals whose bite forces were estimated later to be far, far greater than any estimated bite force for
Dunkleosteus. These include not just
T.rex (higher estimates already known at that time), but also
Giganotosaurus,
Kronosaurus,
Pliosaurus kevani,
Basilosaurus isis, the Great White shark,
O. megalodon, Saltwater and Nile crocodiles, Alligators
, Deinosuchus and
Zygophyseter. Those are just the ones that have higher published estimates or measurements, from which one can infer with a good deal of certainty that other giant predators
(e.g. Livyatan, various megatooth sharks, various giant mosasaurs, pliosaurs and ichthyosaurs) likely also exceeded the bite force of
Dunkleosteus by a fair margin (as would large ceratopsians and likely a few other large herbivores).
---
Anderson, P.S.L. and Westneat, M.W. 2009. A biomechanical model of feeding kinematics for Dunkleosteus terrelli (Arthrodira, Placodermi). Paleobiology 35 (2): 251–269.
Anderson, P.S.L.. L. and Westneat, M.W. 2007. Feeding mechanics and bite force modelling of the skull of Dunkleosteus terrelli, an ancient apex predator. Biology Letters 3 (1): 76–79.
Engelman, R. 2023a. Giant, swimming mouths: Oral dimensions of extant sharks do not accurately predict body size in Dunkleosteus terrelli (Placodermi: Arthrodira). PeerJ 11: e15131.
Engelman, R.K. 2023b. A Devonian Fish Tale: A New Method of Body Length Estimation Suggests Much Smaller Sizes for Dunkleosteus terrelli (Placodermi: Arthrodira). Diversity 15 (3): 318.
Erickson, G.M., Kirk, S.D.V., Su, J., Levenston, M.E., Caler, W.E. and Carter, D.R. 1996. Bite-force estimation for Tyrannosaurus rex from tooth-marked bones. Nature 382 (6593): 706–708.
Meers, M.B. 2002. Maximum bite force and prey size of Tyrannosaurus rex and their relationships to the inference of feeding behavior. Historical Biology 16 (1): 1–12.
Wroe, S., Huber, D.R., Lowry, M., McHenry, C., Moreno, K., Clausen, P., Ferrara, T.L., Cunningham, E., Dean, M.N. and Summers, A.P. 2008. Three-dimensional computer analysis of white shark jaw mechanics: how hard can a great white bite? Journal of Zoology 276 (4): 336–342.
