Slow lorises are one of the world’s only venomous mammals | Hacker News Reader

Slow lorises are one of the world’s only venomous mammals

nytimes.com

52 pointspseudolus39 comments

There is a meme in the carnivore community that animal products are healthier by default, as most plants defend themselves with toxic chemicals and most animals do not. The evolutionary explanation is that animals can usually defend themselves by running away and/or use of claws or teeth. Plants (and fungi), stuck in one place, have to resort to chemical defenses.

Slow loresis reinforce this story by being such a rare toxic exception among mammals, and by being slow, so less able to defend themselves by flight.

Their venom probably isn't even toxic if ingested. The lorises must swallow quite a bit of their own venom given the delivery mechanism.

Venom isn't normally toxic if you ingest it,unless you have internal wounds that would allow it into the blood stream etc.

Poisons are the toxic ones when ingested.

It depends if it doesn’t gets neutralized by your stomach acid and can be absorbed by your intestines it will hit your blood stream.

Since most (if not all) animal venoms are proteins they’ll probably will be broken down by your saliva and stomach acid, tho I wouldn’t consider drinking them especially in high enough amounts to be safe even without wounds.

What is interesting is that they are not slow at all. They can be extremely fast when they know the territory and feel non threatened.

But for you to observe them at the jungle moving fast you have to be very quiet.

They move slowly when there are perceived threats so you don't see them in the jungle.

That is interesting. I move extremely fast only when I feel threatened. I wonder if lorises switch to moving extremely fast when they know that a predator has spotted them.

What’s really funny about this is that the clear area where this isn’t true is seafood. The sea is absolutely loaded to the hilt with things that are incredibly toxic, completely inedible, or entirely unpalatable. There’s a ton of fish that we do eat, naturally, but there are tons of things in the sea that you shouldn’t touch, or that have to be handled carefully lest it kill you.

That’s funny because generally speaking ancient humans preferred seafood over hunting mammals, both because that allows you to be stationary, and because mammals have a disturbing tendency of hunting you back.

Uh, I don't eat the poisonous parts of plants? I use a knife to achieve this most of the time. I also don't eat the digestive tract of animals.

I would have put money on those being found in Australia. Seems like everything venomous lives there. I would have lost - South Asia.

Don't despair, Australia still has venomous mammals, namely male platypuses (platypi?)

platypodes, obviously

platypus has always felt like moose to me, in that it's its own plural.

probably just because it ends in an "s" tho. how dare it do that.

Other than lorises and platypuses (for the armchair pedant -- platypodes), the only other clade of venomous mammals I know of are the solenodons of Cuba and Hispaniola.

I remember learning as a child that some shrews are venomous.

> Shrews are unusual among mammals in a number of respects. Unlike most mammals, some species of shrews are venomous. Shrew venom is not conducted into the wound by fangs, but by grooves in the teeth. The venom contains various compounds, and the contents of the venom glands of the American short-tailed shrew are sufficient to kill 200 mice by intravenous injection. One chemical extracted from shrew venom may be potentially useful in the treatment of high blood pressure, while another compound may be useful in the treatment of some neuromuscular diseases and migraines.[10] The saliva of the northern short-tailed shrew (Blarina brevicauda) contains soricidin, a peptide which has been studied for use in treating ovarian cancer.[11] Also, along with the bats and toothed whales, some species of shrews use echolocation. Unlike most other mammals, shrews lack zygomatic bones (also called the jugals), so have incomplete zygomatic arches.

https://en.wikipedia.org/wiki/Shrew

NYTimes has an article on the Solenedon: https://www.nytimes.com/2019/12/01/science/solenodons-venom....

Are Monotremes mammals?

They are indeed.

Short answer: Yes.

Longer answer: discrete categorization of life is going to be messy, but that's our fault; humans are obsessed with discrete classification and attempt to apply such classifications to systems which aren't so simple. Clearly monotremes are similar to other mammals in many respects but very different in others. In trying to determine whether or not platypuses are mammals, you're really question the nature of the manmade discrete category of 'mammal', not the nature of platypuses themselves. Platypuses remain the same no matter how we choose to classify them.

Super-great answer. And applies to all animals of any stripe. And plants, fungi, bacteria, archaea, and viruses.

Are peaches and cherries the same species? What definition would you like to use?

Cabbage and broccoli? Yes.

West and east African elephants? No, it turns out.

Quaggas and zebras? Yes, it turns out.

Yes.

But all surviving monotremes live in and around the water, in places where they mostly compete with marsupials. Marsupials have an advantage on dry land. But if a marsupial mother with babies in her pouch swam, she'd drown them. So monotremes have an advantage in the water.

Placentals, of course, usually outcompete both. With occasional exceptions, such as the success of opossums in North America.

  > all surviving monotremes live in and around the water

Wait, what? The surviving monotremes are the platypus and several species of echidna. The echidnas are woodland animals without any particular aquatic adaptations.

Eurasia has some aquatic shrews also able to produce a neurotoxin.

> Scientists know of just five other types of venomous mammals: vampire bats, two species of shrew, platypuses and solenodons (an insectivorous mammal found in Cuba, the Dominican Republic and Haiti).

Is there any type of pedant that isn’t an armchair pedant?

A pedant who uses a standing desk.

From: "Are slow lorises really venomous?"[1]

In primates, slow lorises (genus Nycticebus) are though to be venomous in Thai folklore (Wilde, 1972) but are they really?

...

To answer this, let's revisit the definitions of venomous and poisonous. A venomous animal injects toxins into its victim's body by bite or sting. A poisonous animal, on the other hand, produces toxins that are poisonous once inhaled or ingested. Medical literature shows that human - slow loris injuries come from slow loris bites and not from ingesting their toxins. So are slow lorises venomous? Well, not quite.

...

Reports of slow loris bites are rare in literature. However, based on these published reports, it seems that slow loris bites are not venomous (Kalimullah et al., 2008; Wilde, 1972). Due to the high degree of similarity between the brachial gland exudate of slow lorises and the Fel d 1 allergen in domestic cats, the anaphylactic shock expressed by victims is probably just a reaction to the exudate's allergen.

[1] - https://primatology.net/2010/10/19/are-slow-lorises-really-v...

I’m not sure what point you’re trying to make with this comment.

If you’re to point out that Slow Lorises aren’t venomous, then you’ve quoted the wrong part of that article. Your quote only setups the proposition and ends with “not quite” without actually explaining why they are “not quite” venomous. The section just after is the most interesting part.

> Slow lorises have needle-like teeth called dental combs or tooth combs on their lower jaw. Paired with the constant licking of the brachial gland, it is not surprising that one would assume the dental comb plays a part in injecting brachial gland exudate into unsuspecting victims (Hagey et al., 2006). However, this is not the case.

Used for grooming, dental combs might look menacing to some but their function is less sinister than one might conjure up. A bite from a slow loris is painful due to their sharp pointed teeth. Illustration of slow loris teeth from Loris Conservation. The dental comb is on the lower jaw, shape like a spade.

Wilde (1972) reports that the victim of a slow loris bite immediately succumbs to anaphylactic shock (extreme allergic reaction) followed by hematuria. In spite of that, the victim fully recovered. There is no clinical evidence of toxic substances in slow loris saliva to support the notion that they are venomous (Wilde, 1972).

But even then, the article is only looking at very old studies that examine Slow Lorises bites in humans for which there is very little data. Whereas the entire thrust of this article is that Slow Lorises bites are primarily used as a weapon again other Slow Lorises, rather than a defence against predication.

In short I question the relevance of your comment and quote to the posted article. It’s obviously tangentially related, but it seems to be making a point about the least interesting part of the article.

The secretion from the brachial gland of captive slow lorises is similar to the allergen in cat dander, hence the secretions may merely elicit an allergic reaction, not toxicosis.[120] Loris bites cause a painful swelling, and the single case of human death reported in the scientific literature was believed to have resulted from anaphylactic shock.[121] Slow lorises (of the genus Nycticebus) are accepted as the only known venomous primate. Slow loris venom was known in folklore in their host countries throughout southeast Asia for centuries, but dismissed by western science until the 1990s.

yet again the new york times- hyperbole, bad journalism

I was amazed to learn that the common ancestor of all mammals almost certainly had poison spurs in its back legs.

Almost every lineage abandoned venom. Most that have it today evolved it again after losing it.

I think platypuses might be the only lineage that retained it.

It might be interesting to see a comparison of other venomous species: snakes, frogs, insects, reptiles, spiders or is this too far-fetched?

Poor Maaf :(

Some dog farts are definitely poisonous.

> Slow lorises are one of the world’s only venomous mammals (nytimes.com)

a better title might be

Slow lorises are one of the world’s few venomous mammals (nytimes.com)

"one of the only" implies more extreme scarcity than "one of the few", so unless there is some other grammatical consideration I'm missing, saying "one of the only mammals" seems to point more to there being only a handful of species (less than a dozen in total?), while "one of the few mammals" might imply that we're talking about there being few such individual creatures around (which while probably also true I don't think is meant as the focus).

Literally taken, "one of the only" is an oxymoron. They're either "the only" (no "one of") venomous mammal because there are no others, or there are others in which case they're "one of the few" or "one of the many" depending how many others there are.

At any rate, there are a bunch of search results for "one of the only" saying it's a neologism with the same meaning as "one of the few". So we're probably stuck with it now, just like we're stuck with "begs the question" used to mean "raise the question" and "two times longer" used to mean "two times as long".

"leverage" used as a verb bugs me the most. The "-age" suffix is clearly established as a way to form a noun, in this case with the base verb "lever".

If we treat "leverage" as a verb, "leverageage" is valid.

"Lever" is already a noun."Lever" is the tool, "leverage" is what you get by using the tool.

You can debate whether "leverage" comes from the noun or verb form of "lever" (which both exist, and the "-age" pattern is used for both nouns and verbs), but the main point is that "leverage" used as a verb breaks prior usage of "-age" in exactly the way I described.

"leverage" has been used as a noun for centuries, but as a verb for only decades. It's a recent neologism.

I.e. a neologism.

Reply on news.ycombinator.com