As I have already posted,
it appears that we may have a population of giant sloths in North
America. It is an extraordinary creature and it appears to be
solitary for now, but on the basis of less than half a dozen separate
sightings, it is premature to make that statement. This last report
posted two days ago was very important, not least because it once
again provides an extensive collection of witness information. Their
misfortune was that their cabin encroached directly on the territory
of one of these creatures and they then triggered a response.
First though, this
creature is extremely dangerous in quite the same way that a grizzly
is dangerous when disturbed. It needs to be observed with great
caution. There are not a lot of these around, but you can bet their
population is growing and they will become more noticeable. Until
now it has been easier to assume a bear has been encountered and
anyone unlucky to cross their path likely failed to survive.
From my post the other
day:
1 It is fully furred and the fur is comparable to a bear causing natural misidentification from a distance.
2 It is a large creature
that approaches the size and bulk of the Sasquatch. It is able to
take down large herbivores.
3 All limbs sport long
cutting claws with gripping ability for tree work and proficient
digging. This is a very dangerous creature, certainly as compared to
a Sasquatch.
4 It travels on four
legs but easily rotates to the erect stance when attacking or
confronting anything.
5 It has a long snout
and long fangs designed for tearing meat from game. I only have one
report regarding fangs, but otherwise I still think the creature is
normally a herbivore first in quite the same way as other sloths. It
is quite possible that the giant sloth developed fangs in quite the
same way as isolated populations of deer will develop fangs when
ample game is available.
6 It stinks because
fecal matter get caught in the fur and rots and the creature is
possibly unable to easily groom itself in that location.
Alternatively, the fur simply accumulates sweat and oils throughout
the year.
In short, it is a killing
machine from our nightmares that is wonderfully adapted to take to
the trees when threatened and for gaining a perfect hide to stalk
game.
Now what else did we
learn here? It is actually quite a lot.
1 It tears game apart in
what may be described as a killing frenzy. This makes it
particularly dangerous.
2 It eats some of the
game and then caches the rest by burying it. This explains its
interest in grave yards were it is able to smell decomposing meat.
3 It easily excavates a
earthen den to den up in when sleeping. Because sloths need a long
time digest plant material, it will typically slip into a month long
dormant stage to do this. It has a much lower metabolism that we
expect. Yet to prosper when it is about, meat protein is likely
necessary. Winter may make it mandatory as these creatures have been
possibly noted in New Hampshire.
I will now make a major
conjecture. Although fangs have been noted, the creature is poorly
adapted for eating meat in other that gobbets torn of the carcass and
also can only eat a small amount at one time. After all its
metabolism is very slow. What it is able to do is eat maggots. Thus
it creates individual caches of buried meat which is inevitably a
breeding ground for maggots upon which the creature can feed. Thus
we get the noted odor of dead meat around this creature.
I want to note that
maggots feeding on a carcass will take on the taste of the meat it is
eating. This happens to also be used by the Eskimos at least
occasionally in emergencies and possibly more often when a cache of
caribou is left far too long.
Thus we have a predator
that needs to operate within a small hunting range that dens up most
of the time and hugely extends the usefulness of a kill by exploiting
the produced maggots.
It is also nocturnal as
are most predators. Thus it will be dened up during the daytime and
considering the reports on its home ground, most interlopers would
become nervous and be scared of.
If one is hunting for
such a creature, be certain to search up wind and look for the smell
of dead meat. Never approach from the other direction. Way more
important though, scout all trees around yourself from the top down.
That is were it is most at home.
This creature has not
been hunted or trapped because it is too much for a lone individual
to tackle and this would be sensed by an experienced bush man who
would shy off just as these reports make clear.
Other key quotations:
“several tales of a wolf like creature that stood on two legs that would come out of the thickets and attack their cattle and live stock. Day or night. A creature that was taller then an average man by well over a foot, nearly 7 foot tall, with thick long hair covering it's body, and a stench that matched that of some of the freshly open graves that were discovered now and then. This 'wolf man' left tracks like a barefoot man but where the toes should have been, instead were paw prints. The head was huge and wolf like in appearance, with an extra long snout, and uncanny long sharp incisors that glistened from the moon light with saliva, along with eyes that, "Radiated red, like one of the hottest fires in Hell', they'd say. It had long arms that ended with huge hands and long spindly fingers with long, pointed, dirt caked claws”
“had went down in the
woods earlier that morning and found several pits dug and filled with
animal bones and parts of carcasses along the path that led to the
old sawmill that couldn't be explained. There were also holes dug in
the sides of the bluff along the hills that over-looked the old mill
that looked like deep caves, big enough for a man to hide in''
‘Megatheria’
muzzles provide clues to giant ground sloth diets
Posted by Brian
Switek on May 10, 2010
###
The skeleton
of Megatherium, as figured in William Buckland’s Geology
and Mineralogy Considered With Reference to Natural Theology.
There is something
fantastically weird about giant ground sloths. Creatures from a
not-too-distant past, close enough in time that their hair and hide
is sometimes found in circumstances of exceptional preservation,
these creatures have no living equivalent. Their arboreal cousins
still live in the tropics of the western hemisphere, but they can
hardly be considered proxies for the ground sloths of the
Pleistocene.
The most famous of
these ancient beasts was Megatherium, an exceptionally large
ground sloth which has been fascinating paleontologists and the
public for over 200 years, but what is less well known by members of
the public is that there were many kinds of ground
sloth. Megatheriumwas not a lone aberration but a part of a
highly successful family, one of the few types of weird South
American mammal that flourished in North America when the two
continents came into contact a few million years ago. Not all of them
were the same. While some made their living grazing in open habitats
others preferred to browse among most forested environs, and a recent
study published in the Journal of Morphology provides a way
to tell which kind of lifestyle particular sloths might have had.
###
Restoring the head
of Megatherium americanum. A) Skull B) Skull with nasal
cartilage C) Skull with cartilage and muscles D) Full head
restoration. From Bargo et al, 2006.
Everybody knows that
teeth can often tell you quite a bit about what an animal eats, but
it is not the only informative parts of the skull when it comes to
diet. To ascertain the range of dietary habits in giant ground
sloths, researchers M. Susana Bargo, Nestor Toledo, and Sergio
Vizcaino looked at the muzzle shapes of the species Megatherium
americanum, Glossotherium robustum,Lestodon armatus, Mylodon
darwini, and Scelidotherium leptocephalum, a selection with a
variety of skull shapes. Two of these, Glossotherium and
Lestodon, had squared-off muzzles, and the rest had more narrow
snouts, but to determine how this related the diet the authors looked
at the muscle scars and other landmarks in comparison with the known
tissue anatomy of living sloths in an attempt to recreate the soft
tissues of these animals.
As illustrated by the
restorations of the head of each sloth, figuring out their muzzle
shape was a multi-step process. First was determining the extent of
nasal cartilage that would have been present in life. This provided
the complete framework on which to place the various muscles related
to lip movement, and from there the head could be fully fleshed out.
Once these restorations were completed it could be further
hypothesized whether each species was a browser or grazer, with
grazers being characterized by having wide, squared-off muzzles
suited to taking in low-quality foods (i.e. grass) in bulk and
browsers having narrower muzzles better suited to more selective
feeding on high-quality foods.
###
Restoring the head
of Glossotherium robustum. A) Skull B) Skull with nasal
cartilage C) Skull with cartilage and muscles D) Full head
restoration. From Bargo et al, 2006.
The results were
fairly clear cut. Lestodon armatus and Glossotherium
robustum both had comparatively wide, spoon-shaped muzzles,
with Scelidotherium leptocephalum, Mylodon darwini,
and Megatherium americanum having narrow muzzles (the
latter species having the narrowest of all). Overlain on top of each
other, there is a wide gap between the muzzle shape of the grazers
and browsers; the sloths selected are not grades between one extreme
and another but occupy opposite, well-defined ends of the spectrum.
Additionally, Megatherium americanum may have been such a
specialized feeder that it had a prehensile upper lip akin to what is
seen in the black rhinoceros which it could have used to grasp and
selectively tear off particular plant parts. The grazing
sloths Lestodon and Glossotherium, on the other hand,
would have had lips more like that of the white rhinoceros –
squared off and better suited to bulk feeding.
###
An overlay of ground
sloth muzzle shapes, showing a clear division between browsers and
grazers. From Bargo et al, 2006.
The hypothesized
feeding habits of these sloths are consistent with what is seen in
living herbivores – browsers and selective feeders have narrower
muzzles than grazers within lineages of plant-eating mammals. This
may have been a form of niche partitioning as sloths evolved through
the Pleistocene, and may explain why there were so many genera and
species present at the same time. Even though we think of modern
sloths as peculiar, specialized animals, the ground sloths of old
appear to have been more adaptable to a wide array of habitats,
though this makes their disappearance in relatively recent time all
the more mysterious.
Post script: This kind
of niche partitioning did not only exist between closely related
species, but could also happen within species as organisms grew up. A
recently-described juvenile Diplodocus skull,
for instance, suggests that young individuals were browsers while
adult Diplodocus were better suited to grazing.
Bargo, M., Toledo, N.,
& Vizcaíno, S. (2006). Muzzle of South American Pleistocene
ground sloths (Xenarthra, Tardigrada) Journal of Morphology,
267 (2), 248-263
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