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Meet the slow loris, the only venomous primate in existence - Stephanie A. Poindexter
Meet the slow loris, the only venomous primate in existence - Stephanie A. Poindexter
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Phụ đề (76)
0:16
Deep in the jungles of southeast Asia lurks a deadly creature
0:20
with sharp teeth and a venomous bite:
0:23
a slow loris.
0:24
Despite their wide-eyed looks,
0:27
their story is much fiercer than you might imagine.
0:30
Lorises split off from other primates as far back as 70 million years ago,
0:36
when T-rexes still roamed.
0:38
And they gradually migrated from Africa to Asia.
0:43
Around sunset each evening, lorises get active,
0:47
moving slowly and deliberately through the trees in their home range.
0:52
They use their large eyes to scan their surroundings for their next meal
0:57
and take little time to rest.
0:59
Pygmy lorises, for one, regularly pass their nights in near-constant motion.
1:06
Unlike many other primates, however,
1:08
slow lorises have a higher proportion of slow-twitch muscle fibers,
1:13
which are favored for long-winded exertion versus speedy spurts.
1:19
They also have extra vertebrae, making them especially flexible.
1:25
When needed, slow lorises can stay still, gripped to one tree branch for hours,
1:31
extra blood vessel networks in their limbs
1:34
preventing them from weakening or becoming numb.
1:38
Their slow movements help them go undetected.
1:42
And that way, they avoid threats,
1:44
staying stealth around predators that tend to be on the lookout for motion;
1:50
and they can better hunt unsuspecting prey.
1:54
Slow lorises are omnivores that go after lots of insects
1:59
and other small animals, as well as fruit and nectar.
2:03
Interestingly, they also consume a lot of tree gum and sap,
2:08
scratching at tree bark with a row of specialized teeth called a “toothcomb.”
2:15
Though these plant substances are tough to digest,
2:18
slow lorises seem to be well-equipped to detoxify them.
2:24
Some scientists even suspect that they sequester the toxins
2:28
from the tree gum they devour
2:30
because slow lorises are, in fact, toxic themselves.
2:36
They’re the only venomous primates, and one of only a few venomous mammals.
2:42
And their venom system is thought to be one of the most complex
2:46
in the animal kingdom.
2:48
It works in two parts, with the combination of two separate secretions.
2:54
When threatened, slow lorises may assume their venom pose,
2:58
raising their arms so they can easily access glands near their armpits
3:04
that secrete a toxic oil.
3:07
When they lick at the glands, the oil combines with their saliva
3:12
to form their formidable, flesh-rotting venom.
3:17
They store the mixture on their sharp toothcomb,
3:20
to be deployed with a bite capable of causing intense pain, tissue damage,
3:26
anaphylaxis, and, in small animals, even death.
3:31
Slow lorises spread the oil over their coats where it can kill parasites
3:36
on contact.
3:38
In fact, the number of parasites they carry on their skin and fur
3:42
is remarkably low relative to other primates.
3:46
And it may also be protective against bigger threats.
3:50
When slow lorises sleep, they curl into little balls,
3:54
toxic coats exposed, perhaps to help deter predators.
3:59
Cats, sun bears, and civets are repelled by just the scent of slow loris saliva—
4:05
though orangutans seem to have found a way around it.
4:09
The most common victims of slow loris bites, however, are other slow lorises.
4:15
Tracking one population over the course of eight years,
4:19
scientists only recorded one slow loris dying from natural predation.
4:26
But 20% of them got bitten by other slow lorises,
4:30
perhaps in fights over limited territory.
4:33
And while they may look cute to us,
4:36
those same features might send a very different message to predators at dusk.
4:42
When in danger,
4:43
slow lorises may assume their venom pose, sway, and make a raspy noise.
4:49
Some scientists think these behaviors and their markings
4:53
might help them effectively mimic spectacled cobras.
4:58
This could be an example of Müllerian mimicry,
5:02
where one dangerous species benefits from sharing certain characteristics
5:06
with another,
5:07
helping warn other creatures to stay away.
5:11
But if slow lorises evolved to look like cobras,
5:15
we don't seem to be getting the memo.
5:17
Though every species of slow loris is threatened,
5:21
humans continue to illegally trade them as pets,
5:25
stripped of their natural defenses, their teeth cut or pulled.
5:30
It’s well past time to pick up on the signals they’ve been sending
5:34
and leave the fierce slow loris— and their forests— alone.
