Tuesday, February 20, 2007

Really Honkin' Big Animals

Dear Constant Readers,

Being an American, I am stereotypically obsessed with all things gigantic. Also being rather fascinated by Animalia both extinct and extant, it was only a matter of time before a post like this got written. The genesis of this post was Amphicoelias fragillimus, apparently the biggest honkin' dinosaur of them all. See Darren Naish and the Hairy Museum of Natural History for very good posts on this subject. Also thanks to Amber Alborg, for one of the most hillarious adjectives I've ever heard of.

Also please note that animal sizes tend to be exaggerated, if you know for a fact that some of these records are a load of crap, let me know. The last thing I want to do is spread around more crappy information on the Internet! This list isn't meant to be authoritative, but if there are any records I overlooked that really should be on here, give me a shout.

On all "illustrations", please note that I stand a towering 5'8.5" (1.74 m). If you're an average Italian male, that should roughly be your height according to Wikipedia. Just thought you should know.


Primates

Our species has quite the impressive range; from 1'8" (50 cm) and 5.5 pounds (2.5 kg) [both Lucia Zarate] to 8'11" (2.72 m) [Robert Wadlow] to 1400 pounds (636 kg) [Jon Bower Minnoch, no picture needed] or even 1600+ pounds (727 kg) if Wikipedia is to be trusted. The tallest non-pathological giant was Angus MacAskill, standing 7'9" and weighing 425 pounds. He was allegedly monstrously strong too, capable of lifting a 2800 pound anchor. That seems far-fetched to me, but his size was real enough for Guinness to include him when their categories were broader. Then there was Mills Darden, who allegedly combined obesity and gigantism, supposedly weighing in at ~1000 pounds and standing 7'6". He was also in Guinness, but his case is less documented and outrageous sounding. Even if there is some exaggeration, our species has quite a shocking range for not being much bigger than chimpanzees on average.

Gorillas are pretty big honkin' animals...for primates at least. Sure they're only in the 5 foot range (1.65 - 1.75 m) while standing (thanks to short legs), but they can still weigh 3-400 pounds (135-180 kg). I think from a human perspective, the overall similarity to gorillas plus the somewhat superhuman size is what makes them impressive. Record sizes are supposedly over 6 feet tall (1.82 m) and 500-ish pounds (227 kg). Obese Gorillas have gotten larger, of course, but they hardly count. The giant lemur Archaeoindris was around the same size, if not larger than the gorilla average at 440 pound (200 kg).

But of course, both of these pale in comparison to the fossil ape Gigantopithecus. Originally thought to be a giant related to man (more on that later), it turned out to be a pongid ape related closer to Sivapithecus and Orangutans than anything else. In the wack world of Cryptozoology, it is seen as a candidate for Bigfoot, despite the likely quadrupedal stance and inferred great size. That's right, there unfortunately isn't much in the way of fossils for this species. Unlike other big jawed hominids (i.e. Paranthropus), this one apparently had a jaw to match the body. Grover Krantz's reconstruction pegged the skull at an astounding 15" high, and I think a recent reconstruction by Ciochon made it even larger (I can't remember where the source is for the life of me). But body reconstructions peg it at around 9-10 feet (~3 meters) and a weight estimate of 600-1000 pounds (300-500 kg). This does sound a little light actually, since a 4.5 foot (1.37 m) Orangutan weighing 180 pounds (81 kg) would scale up to around 1500+ pounds, and a gorilla even more so. That's another American trait, even though I didn't write the paper, I still think it's my God-given right to nitpick needlessly.


Birds

One of the most impressive animals, I think, it the Marabou stork. It's ugly as hell , stabs flamingos to death, can eat butcher knives without ill-effect, joins vultures at carcasses, etcetera. It seems like quite the sort of animal to survive for a while no matter what people are doing to the planet...which makes it troubling why it's close relative the Greater Adjutant is doing so poorly. What makes the animal impressive is it's size, roughly 5 feet tall, 20 pounds, with a wingpan that can reach over 9.5 feet. What's really shocking is that there's a record for a Marabou shot by Richard Meinertzhagen in 1934 of...13 feet 4 inches. Another claim made in old editions of Encyclopedia Britannica mentioned a Greater Adjutant 7 feet tall, which would make it proportionally similar. If these claims are to be believed, the Marabou and Adjutant would hold the records for largest wingspan for any bird, the tallest birds, and presumably the heaviest birds too. Leptoptilos titan ("much larger than living adjutants") and Leptoptilos falconeri (6'6"/2m, 45lbs/20kg average) were prehistoric species in the same size class as the uppermost Marabou and Adjutant claims; so even if the modern claims are exaggerations, there were (not-too-distant) prehistoric birds that size. And who knows how big the freaks of those species were.

An extremely artistic depiction of me and a super-Marabou. Image source from here.

Possibly related to the gigantic storks and modern day condors and New World Vultures was a group of birds called the Teratorns. [Correction: The scoundrelous Darren Naish has ruined my fun and pointed out that storks and the vultures/teratorns aren't that closely related.] Often and dubiously portrayed as super-condors, they were likely fairly active predators with a tendency to hunt on their prey on the ground. However, the largest species, Argentavis, may have in fact been a scavenger after all. A presise size estimate is not readily apparent, but it is estimated to have been between 140 and 260 pounds (65 to 12o kg) with a wingspan of 21 to 23 feet (6.5 to 7 m). Even though the current opinion is that this is some sort of mega-vulture, it's still a pretty impressive bird with a head the size of a horse's. I just wish there were better images of it online as to compare myself to.

While Argentavis may have stretched imaginations for how big birds can get, other fliers were out there that were so big, they were almost other-worldly.


Pterosaurs

The fossil species Pteranodon has a wingspan about the same as that of Argentavis, 20-25 feet (6-7.5 m), but that isn't too big a deal in the Pterosaur world. Sure it probably weighed a great deal less than Argentavis, but it was probably just as striking. And what's interesting is that at one point of time, this was thought to be the upper limit for fliers. As it turns out, the upper limit keeps on getting pushed up; Quetzalcoatlus famously pushed it to an unbelievable 40 feet (12 m). And not only that...their anatomy was just so implausible and other worldly looking that...well I can't describe it with words. Behold one of the most impressive illustrations I've seen, from Mark Witton's flickr site:


The sheer ludicrousness of this animal is beyond words. And this isn't the only species of pterosaur to get this large, the Romanian Hatzegopteryx thambema was around the same size...but had a head nearly 10 feet (3 m) long! That's the longest head of any non-marine animal...on a flying creature. These creatures, along with other giants such as Arambourgiana, are called azdarchids, the largest and last of the pterosaurs. Here's the inevitable link to Darren Naish's blog illustrating that they were in fact in a niche similar to storks...but much larger. And what's amazing is that now the max estimate has been recently kicked up to...60 feet (18 m) from remains found in Mexico. Here's the expected link to the Hairy Museum of Natural History. Now, do I dare "update" the picture...assuming normal proportions and all...to attempt to illustrate the vastness. Well, let me just plug Mart Witton's flickr site one more time and I think it'll be fine.

What can I say, I feel even less significant than normal. Note that I played around with the anatomy, making it more robust overall as big animals tend to do.


This really does make me wonder about the limits that biomechanics impose. It makes me wonder about one question in particular...


[Correction: Darren Naish strikes again! The Pterosaur is no more. I leave the strike outs as a painful reminder to myself to stay more on the ball in the future]


Marine Reptiles

How come marine reptiles didn't get really really big? I mean, the sauropods were more massive than the biggest (freak) elephant by a factor of ten, and who knows how many times bigger that hypothetical mega-pterosaur was than the Kori bustard and other "giant" birds. How come the same isn't true for marine reptiles? How come there isn't some ultra-ichthyosaur that puts the blue whale to shame? Even though I eagerly await the day there's some 200+ ton marine reptile in the books, the ones out there aren't too bad. I mean, they're far bigger than any animal I've had on here so far, so don't be confusing them for unimpressive.

Fortunately for me, National Geographic has given them a recent treatment which, I think, probably beats my good ol' outlines. They seemed to have covered all bases, even covering the super-gigantic Shonisaurus sikanniensis, the largest known marine reptile at an incredible 70 feet, putting it into the whale leugue. But...I think some giant pliosaur fans might be a tad...confused at their favorite animal not getting mentioned. In the BBC documentary there was an 80 foot (25 meter) Liopleurodon weighing 150 tonnes (~160 tons) pretty much just hyped as the biggest marine predator ever. Problem is, there's nothing really to indicate that Liopleurodon got even half that length, actually they seemed to top out at a mere 33 feet (10 meters). But looking at the animal, already the size of a big killer whale, it would have been quite an intimidating predator. Do we really need to exaggerate these animals?

While Liopleurodon didn't get enormous, that doesn't mean that other pliosaurs didn't. The "Monster of Aramberri" was a ~50 foot (15 meter) colossus that apparently wasn't even fully grown. Thanks to the BBC special, it was misrepresented as Liopleurodon, but is apparently different. Actually, what's odd is that there was a report of the (allegedly near-complete) skeleton in 2002, but I haven't seen anything recent on it. What species is it? How big was it? Was it in fact killed by a larger pliosaur as I heard? There are some vague mentions of pliosaurs in the same size class if not larger, but none nearing 25 meters. But who knows, they may have gotten that large. Something as big as a rorqual whale but not sustaining itself with suspension feeding may sound extreme, but...look at the sauropods, the pterosaurs, and the gigantic theropods. Judging by the fauna we have to day, they're all completely absurd, yet they existed. It's hard to dismiss anything as implausible or impossible in paleontology.

But the question now is, even if there was a 25m 150 tonne pliosaur, would it have been the biggest "predator" of all time?


Sperm Whales

And here is proof that something doesn't have to be a suspension feeder in order to grow large, although I think the apparent ability to stun prey helps out a lot. They've been known to get up to 60 feet (18 meters) in length with a weight of 55 tons (50 tonnes), making them the 7th largest species of whale (after the blue whale, fin whale, and four right whale species). That's not bad considering the next biggest toothed whale is the Baird's Beaked Whale, at maybe 15 tons tops (beaked whales are cryptic and good future post material). However, there have been old records of very very big sperm whales. Wikipedia mentions lots of stories indicating sperm whales got quite large in the past, implied to be 84 feet (25.6 meters) to even 90 feet (28 meters) in length. Wikipedia is being trustworthy here, as Guinness too has mentioned that the 84 foot estimate stems from a 18 foot long (5.5 m) jawbone in a Nantucket Museum. This should be fairly easy to check, and there seem to be lots of other stories indicating really really big sperm whales. I wish I still had the Guinness book of Animal Facts and Feats as it talked extensively about this, and other animal size records. I suppose it is implied that due to hunting, the average size of the sperm whale has decreased dramatically. This has happened with fish at least, swordfish average size plummeted from 250 to 90 pounds (110 to 40 kg) due to hunting, so this does seem to be a real phenomenon.

This all implies that that the sperm whale really could have gotten nearly as large as the blue whale. A 90 foot (28 m) sperm whale would have to weigh roughly 150 tons (or tonnes), compared to the record 200 ton (180 tonne) blue whale. Of course, who knows if the right whales shrunk significantly too. And I can't help but wonder that since every other animal seems to have larger prehistoric relatives, if there weren't some really really big whales out there too.


Everybody! Everybody!
Left to right, top to bottom:
Hainosaurus
(Mosasaur, 55 ft/17.5 m); Me; Shonisaurus sikanniensis (Ichthyosaur, 70 ft/21m); Blue Whale (110 feet/33m); Hypothetical mega-Pliosaur (60 feet/20m); Hypothetical super-Sperm Whale (85 feet/26m); Right Whale (60 feet/20m); Orca (32 feet/9.75m), Liopleurodon (33 feet, 10m); Large bull Sperm Whale (60 feet/20m).


Huh, well this post took a while and I didn't nearly get to all the really big animals I wanted to. Who knows, maybe a sequel post will be in the works. In the meantime, who knows what I'll be up to next...

Thursday, February 1, 2007

Monkey-Lizards and Birds: One Strange Alternate Theory

Dear Constant Readers,

When I first saw a page about Monkey-Lizards, I thought they were just made up. They were areal and chameleon-like, but had bird-like heads and (occasionally) anteater-like claws. Coupled with the strange name, I thought that they were part of a Spec World type project. How wrong I was. I should learn never to doubt the Hairy Museum of Natural History again! Monkey-Lizards are part of the bizarre group Avicephala, Diapsid reptiles considered by some as the alternate point of origin for birds. While Dinosaur origins are well supported, I like the idea of alternatives such as this post by Darren Naish on an equally strange theory for primates being flightless animals. Sure, they're almost certainly not right, but that doesn't mean that they aren't thought provoking.

There really isn't too much information out there for the poor Monkey-Lizards on the Internet. The most informative pages out there are from the HMNH and this page on Triassic Reptiles (see here too). These animal are generally considered to be highly derived aboreal Diapsids, but there is also theorizing of them being gliders or even aquatic. Coincidentally, one of Bruce Champaign's "Sea Serpent" types is a aquatic chameleon-like creature, which I drew, even more coincidentally. But that's a story for a different day. These creatures also survived the Permian-Triassic extinction, making them considerable for Connor's Island, but again, a story for another day.

The point is, these were some very weird animals. They're Diapsids like most (or all) modern reptiles, and overall somewhat converge upon chameleons. The front limbs had the 3 vs. 2 opposable digits of chameleons, but others had no opposable digits, or a gigantic claw similar to that of a pygmy anteater. The hind feet were somewhat unusual in that some specimens had an opposable digit, while others did not. Apparently, this is a very weird instance of sexual dimorphism, possibly breeding related. The tail was not as flexible in the vertical plane as a chameleon's, but a large hook on the end of the leaf-shaped tail probably compensated for this. Instead of capturing prey with a long tongue like a chameleon, Monkey-Lizards had a fairly long and flexible neck to capture prey, and muscles attached to an odd hump on the back. Strange as all of these features are, the most notable is the head. Instead of being lizard-like or chameleon-like it is bird like or even pterosaur-like. The lacked a fenestra present on Pterosaur heads, but some have argued that it may have secondarily closed. What's that? A potential relationship?

Before I get too caught up, I'd like to point out that most of the reconstructions are copyrighted...so I can't post them here. However, I think I still can give links to them. Vallesaurus. Dolabrosaurus. Hypuronector (aboreal). Hypuronector (aquatic). Hypuronector (skeleton). Drapenosaurus. Drapenosaurus (skeleton). Megalanacosaurus. Megalancosaurus skeleton. Another Megalancosaurus skeleton.

And here's a link to papers on Drepanosaurs/Monkey-Lizards.

So as I implied, there are some that ally the Pterosaurs with the group containing Monkey-Lizards, the Avicephala. It would make sense to link flying animals with aboreal animals/gliders (getting to that), but I think it is mostly based on head structure. It is lacking a fenestra, and bird-like heads have evolved in the bizarre Effigia. Again, more on that weirdo later I'd imagine. So I guess for the time being, Pterosaurs are still too derived to determine where their ancestry is from.

Oh yes, and as I implied, the Avicephalans are also home to the group of the oldest gliding reptiles. Coelurosaurus was all the way from the Upper Permian, and unlike modern gliding groups, didn't support itself with ribs, but bony dermal rods. Obviously a mechanism like this is separate from modern flyers, but it at least demonstrates the tendencies of the group.



Things get very interesting when Longisquama enters the picture. There is a lot of controversy here, so it's going to be hard to try and sum up. It is apparently an aboreal creature with what appear to be "feathers" coming up from the back. These "feathers" or modified scales may also have been used to glide. Problem is, this animal is from the Early Triassic, before birds or even dinosaurs. This animal is sometimes regarded as being an Avicephalan, but opinion varies. Some individuals consider this to be an archosaur (or archosauromorph), but others consider it to be an early...theropod dinosaur! And not only that, but it is also theorized to be ancestral to modern day birds!

Of course, this creates a very interesting situation. Some then theorize that some animals regarded as bird-like dinosaurs are not dinosaurs at all but...flightless descendants of birds, which aren't dinosaurs. So basically, something like Velociraptor or maybe even Therizinosaurs aren't even really dinosaurs, but weirdo descendants from Longisquama. Things like Allosaurus are apparently still dinosaurs that converged upon them. Who knows what Tyrannosaurus, which is more bird-like than Allosaurus but not as bird-y as Velociraptor. I never heard of any clear cut off line, and I think this is the Achilles' heel of the theory. In all likelihood, the people that theorized this were...a little over-enthusiastic in turning all previous thought on its head. But that's how science gets stronger, all the possible theories get questioned and the strong one prevails. Tantalizing bizarre flightless pseudo-dinosaurs may be, it probably belongs in the realm of fiction. See here and here for extensive rebuttals, and Wikipedia for links to the major papers and a good summary.



Bird evolution is very interesting and quite complicated, even disregarding these Avicephalans. There are probably going to be a few more posts on this in the future...but I'm going to have to read up on it a lot before I can talk even somewhat coherently. Stupid reverse-birds and all. Well, more posts in the future, who knows on what.

-Cameron