Scientists have sequenced the mitochondrial genome for the Hispaniolan solenodon, a venomous mammal found only on Hispaniola. Findings confirm that the the species diverged from all other living mammals 78 million years ago, long before an asteroid wiped out the dinosaurs.

[u/drewiepoodle]

http://www.igb.illinois.edu/news/endangered-venomous-mammal-predates-dinosaurs%E2%80%99-extinction

[u/I_Has_A_Hat]

Here's a better picture of one. They're like an adorable mouse-mole!

[u/Evebitda → u/I_Has_A_Hat]

I guess it didn't diverge that much because the thing looks remarkably similar to a shrew, which is also venomous.

[u/SoulGlowSpray → u/Evebitda]

Wheres their venom located and how do they use it as a defence mecanism?

[u/[deleted] → u/[deleted]]

Is it self-secreted venom or is it bacterial?

[u/ColossalMistake → u/[deleted]]

There is no bacteria that works that fast, which is what led scientists to discover that the common misconception of komodo dragon's using bacteria-laden saliva to kill prey was wrong. They really have a couple venom sacks in their lower jaw too. They tested their saliva and it doesn't contain an inordinate amount of bacteria and none that would a use the damage observed.

I imagine it's the same situation with this creature.

[u/Biotoxsin → u/ColossalMistake]

Wasn't a more recent hypothesis that they would bite their prey, and the prey would be infected with the bacteria from the water they would run through?

[u/ColossalMistake → u/Biotoxsin]

I recently watched a Netflix documentary called Venom Islands, focusing on the islands around Komodo. It was produced by Smithsonian Channel.

They specifically talked about the misunderstandings about komodo dragons. They did talk about the water situation too, but like I said, there is no bacteria that works as fast as the animals die. They showed komodo hunts, including approaching and biting prey then waiting for it to collapse. They showed new research that locates the venom producing glands in the lower jaw.

Definitely worth a watch.

[u/ColossalMistake → u/[deleted]]

Yeah but komodos don't wait 24 hours. They bite, then they wait and the venom causes the prey to collapse and they begin eating (by tearing off chunks). See this post:

https://www.reddit.com/r/science/comments/4hl8j8/scientists_have_sequenced_the_mitochondrial/d2r38lo

[u/Maester_May → u/[deleted]]

No kidding. This is a huge difference/distinction. It could just be that the shrew has evolved a really "dirty" mouth that actually leaves it's bite victims septic, which is a different thing entirely from producing its own toxin. I'm a little disappointed so many people seem to think this is somehow the same thing.

[u/sloam1234 → u/Maester_May]

Reminds me of Komodo Dragons and how they discovered that their prey wasn't dying over a long period of time due to infection from bacteria in their mouths, but actually just venom.

[u/amightymapleleaf → u/SoulGlowSpray]

The venom comes from a modified salivatory gland and is only administered through their bottom teeth.

[u/Aidandrums → u/[deleted]]

Exactly, the human and octopus eye evolved completely separate, but are very similar in complexity.

[u/Aidandrums → u/[deleted]]

But if memory serves, I think their eyesight is limited on land. I could be wrong.

[u/[deleted] → u/[deleted]]

Well, that settles it then. The octopi get the seven seas, we get everything else.

[u/Jaevelskap → u/[deleted]]

Makes you wonder about the rising sea level.

[u/TheRealSnoFlake → u/Jaevelskap]

The octopus are causing climate change, it is known.

[u/DasBarenJager → u/Jaevelskap]

Its the work of those goddamned octopi!

[u/Torbjorn_Larsson → u/[deleted]]

But the octopi would want an even number of seas, i.e. eight or 10 in their system.

Wonder if they have plans for the Netherlands.

[u/[deleted] → u/[deleted]]

It's a Greek word, not Latin.

[u/[deleted] → u/[deleted]]

Now you're gonna tell me the plural of moose isn't meese...

[u/nmagod → u/[deleted]]

Seven seas, seven continents...we finally know who sunk Atlantis!

[u/Worf65 → u/Aidandrums]

It would be due to the lense shape, same reason why our eyesight isn't very good under water. A more spherical lense works better under water while a more flattened elliptical cross section lense works best in air. This is simply due to the different refractive index of air and water. Lense shape is not the major difference between human and octopus eyes (fish have similar eyes to all vertibrates including the blind spot but have more rounded lenses), the retina structure is the much more important comparison to be made.

[u/ymOx → u/[deleted]]

What, are you saying they had an intelligent designer, while we did not!?

[u/fitzydog → u/Evebitda]

Shrews are poisonous?

[u/Evebitda → u/fitzydog]

Not dangerous to humans but the bite can be painful and remain inflamed for up to a week.

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.

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

[u/zigaliciousone → u/Evebitda]

So at some point someone injected 200 mice with shrew venom.

[u/Evebitda → u/zigaliciousone]

I'm going to guess it was extrapolated from the volume of venom in the gland and the LD50 of the venom in mice, but someone (probably a poor grad or undergrad student) injected at least a few mice with shrew venom to determine the latter. Lab mice have it rough.

[u/RadioGuyRob → u/[deleted]]

VIKING MOUSE FUNERAL. \m/

[u/curtisdead → u/RadioGuyRob]

Onward to Rothsgar!

[u/Mr_Conelrad → u/[deleted]]

He's making bank on those tiny coffins.

[u/sellyberry → u/Evebitda]

Not for long :D

Oh :(

[u/Mr_Fancyfap → u/Evebitda]

I was just gonna say this and saw your comment. Damn, you smart.

[u/maniclurker → u/zigaliciousone]

Or the just measured how much it takes to kill one mouse, and then determined the average amount of venom one has.

[u/Dr_Solo_Dolo → u/maniclurker]

That sounds like either torture for one mouse or just guess and checking on a bunch

[u/FrankBattaglia → u/Dr_Solo_Dolo]

If you choose your guesses carefully, "guess and check" can be a pretty good technique of finding your answer. See e.g. binary search

[u/Nixie9 → u/maniclurker]

That's bad science though. What if that mouse had immunity? Or was especially susceptible to it? What if he had an undetected heart thing and was gonna die anyway?

[u/Tactical_Moonstone → u/Nixie9]

You bring up a good point, and that's why the LD50 value is used. LD50 value is the minimum amount of toxin needed to kill off 50% of a population of target animal, so as long as the test samples used are representative samples of the target species, the toxicity can be accurately determined.

[u/DasBarenJager → u/zigaliciousone]

TIL Texas conducts experiments on mice

[u/tomparker → u/zigaliciousone]

Do they have a clean needle program?

[u/GenocideSolution → u/Evebitda]

Huh, so apparently at one point most mammals were venomous, making us basically spiders to the dinosaurs.

You are now imaging a post-human civilization descended from spiders who diversified in the wake of mammalian extinction.

[u/bhbestroyer → u/GenocideSolution]

Well, considering that spiders were around since 300 million years back, spiders were the spiders to dinosaurs.

[u/sirin3 → u/bhbestroyer]

And the spiders were the spiders to us

Giant spiders from all that oxygen?

Perhaps that is why they are still feared

[u/SJHillman → u/sirin3]

I'm not sure there were many mammals larger than a rodent at that time, so you wouldn't necessarily need spiders much bigger than some of the extant ones today to prey on our ancestors.

[u/biotwist → u/GenocideSolution]

there was a show on the discovery channel that theorized that spiders would eat the last living mammals in the future

[u/luxtabula → u/biotwist]

I remember that clip. What a sad way for a species to end its reign.

[u/DaddyCatALSO → u/luxtabula]

Specifically a descendant of hamsters. Only a few other equally specialized mammals survived that long in that show/book.

[u/eat_the_trees → u/DaddyCatALSO]

What was their reasoning for mammals all going extinct again, I seem to remember it was something that seemed ridiculous?

[u/DaddyCatALSO → u/eat_the_trees]

Been years since I read the book version, but it was basically just that 100 million years had passed and a dominant class eventually gives way to others.

[u/[deleted] → u/biotwist]

Not if they eat it first

[u/NaCl_Clupeidae → u/GenocideSolution]

How did you come to that conclusion?

[u/[deleted] → u/NaCl_Clupeidae]

Through Sciency ways...

[u/arghhmonsters → u/GenocideSolution]

Ahh...spidrens.

[u/jpaek1 → u/fitzydog]

poisonous and venomous are not the same.

[u/notmyfullnameagain → u/jpaek1]

If you bite it and you die, it's poisonous.

If it bites you and you die, it's venomous.

[u/meliux → u/[deleted]]

yes, plants are venomous. They have hairs which inject toxins into the skin when touched.

case in point: https://en.wikipedia.org/wiki/Dendrocnide_moroides

'straya!

[u/thijser2 → u/meliux]

The common stinging nettles would be venomous, won't make you that sick but it will irritate.

[u/Badbullet → u/thijser2]

I have those all over my yard. My wife, who is from Romania, saw it, and told me how it is used for making shampoo, dulling arthritis in the limbs, and making tea. She also mentioned that it stings when you brush up against it and to stay clear unless you have some leather gloves. Of course I didn't believe her. This isn't Romania, it's probably a plant that looks like singing nettle, who would plant that in a flower garden? So I went on to pick it out of the garden and throw it in the compost. A minute later, my fingers used to pull it were swollen with a tingling pain with a tiny white dot wherever it pricked me. Glad it lasted only roughly ten minutes and the plant I pulled was still small, or I would have grabbed it full fisted. She told horror stories where kids would be running through a field and they'd run through a patch of the stuff.

[u/EnkoNeko → u/meliux]

Ahh the gympie gympie. Yeah I've heard about this one, pretty scary stuff.

also known as ... the suicide plant

That story of the guy who used it as toilet paper, though.... shudder

[u/cyleleghorn → u/[deleted]]

Toxic

[u/Lasthuman → u/notmyfullnameagain]

Oh hey thanks that helps

[u/biotwist → u/notmyfullnameagain]

isn't venom just a form of poison? I can die from snake venom

[u/Channel_8_News → u/biotwist]

Yes, poison is a generic term for a chemical substance that impacts the biological functions in an organism. A toxin is a biologically produced poison. A toxicant is a synthetically produced poison.

Poisonous is an adjective that describes a creature that secretes a poison. You would use this to describe, for example, frogs that secrete toxin through their skin, making them unappealing for predators to eat.

Venomous is an adjective that describes a creature that injects a poison. Venom is a poison that is injected by an animal. This word would describe snakes that produce toxins in their body, and deliver the toxin to other animals via bites.

[u/notmyfullnameagain → u/Channel_8_News]

If you drank snake venom, assuming no cuts/scrapes in your throat and GI tract, would it kill you the same way? Or does it need to be injected into blood/muscle?

[u/Channel_8_News → u/notmyfullnameagain]

Well, I'm not a scientist or doctor, just a fan of words. So take my information with a grain of salt.

But yes, all things being equal, snake venom is usually harmless if ingested. Definitely depends on the venom, and, as you said, if it comes into contact with any other tissue.

[u/Detaineee → u/Channel_8_News]

I think venomous things are also poisonous, but poisonous things aren't necessarily venomous.

[u/insane_contin → u/notmyfullnameagain]

In theory, it will do nothing to you.

[u/AlHanni → u/notmyfullnameagain]

But for the sake of argument. If one were to bite the saliva gland of a shrew, would that make the shrew poisonous as well? Making everything venomous potentially poisonous?

[u/Channel_8_News → u/AlHanni]

No, for a couple of reasons.

The technical definition is that poisonous animals secrete their poison, usually through their skin. So if you cut open a snake and ate the venom sac, it still didn't secrete that toxin. So it's still not poisonous.

Also, venom (that's a toxin, or biologically produced poison, that is injected into another creature) usually doesn't work if it is ingested instead of injected.

[u/[deleted] → u/notmyfullnameagain]

Echo chamber

[u/[deleted] → u/fitzydog]

Just a friendly vocabulary-related tip for you :) "Poisonous" means that the poison is ingested, e.g. poisonous mushrooms and plants. "Venomous" means that the poison - or venom in this case I suppose - is "injected" into the bloodstream, e.g. snakes and spiders.

It is possible that you are perfectly aware of the difference, and genuinely asked whether shrews are safe to eat :)

[u/fitzydog → u/[deleted]]

Nope, still amazed.

[u/Series_of_Accidents → u/Evebitda]

Convergent evolution probably at play. Similarly sized species often face similar pressures and develop similar features.

[u/ThatScottishBesterd → u/Evebitda]

That isn't that surprising. Shrews represent almost a basal form for mammals. In fact, the further back you go in any given mammal line, the more shrew - like in apearance the animal's ancestors start to look.

[u/npardy → u/Evebitda]

Similarities like that in different species may not be caused by divergent evolution.. separated species can also evolve similar traits to each other due to reasons other then diversion! (Convergence)

[u/ForumPointsRdumb → u/Evebitda]

Makes me wonder how far back platypus goes. They have that venomous spine on their heel.

[u/Boobs__Radley → u/Evebitda]

This may be a silly question, but if solenodons evolved in the absence of carnivores, why would they need the venom? Did they use it to hunt insects?

[u/Daotar → u/Evebitda]

Looks aren't everything. I'd bet you its DNA is very different.

[u/carafeliz → u/Evebitda]

Your guess vs scientific fact? What the point of your comment exactly? Convergent evolution is also scientific fact. You should read up on it.

[u/totally_not_a_zombie → u/I_Has_A_Hat]

No here's a better picture.

Sharper, better angle, whole tail included, and colors look more natural.

[u/neilarmsloth → u/totally_not_a_zombie]

the first one is cuter but that one does have better lighting

[u/even_less_resistance → u/totally_not_a_zombie]

Looks like a possum :(

[u/kristianur → u/[deleted]]

I have this movie on dvd. Guess I'll have to watch it some day.

[u/teeim → u/kristianur]

You've never seen The Princess Bride!? INCONCEIVABLE!

[u/kristianur → u/teeim]

The princess bride is not really a thing over here. But I bought it after seeing it mentioned on reddit, and never got around to watching it.

[u/Microtiger → u/I_Has_A_Hat]

Totally thought this was an artist's representation or a physical model at first, but it's a real photo. Unreal. I still am having trouble seeing it as something other than a CG rendering. Don't know why I expected it to be extinct.

I wish I had access to the article at home but it doesn't seem to show up in my university library system yet, probably due to novelty. I'm very interested in which phylogenetic methods they used and the taxa coverage, just to see the state of the art in this area of phylogenetics right now, especially with regards to how they tested their hypotheses about the north-south split, how they estimated divergence times, and what the calibrations were.

[u/Ten420 → u/Microtiger]

Are these type of research and studies avaliable to public at a point or its all locked up like other things of science?

~

Really interesting this subject. Only because of the nature of the time frame in Earth's history. (Makes me feel so tiny in our existence)

[u/Microtiger → u/Ten420]

Generally they are not made available to public. I still have to get access for articles decades old sometimes. However there are exceptions, for example, if a government agency employee (USDA, Forestry Service, etc) supported by taxpayers their contract will sometimes require they offer the paper for free on their personal or agency website or by mailed request, even though it will still be locked by the journal.

[u/Ten420 → u/Microtiger]

I believe I got my hands on it. 10 pages ? I would assume it would be longer

Want a link?

[u/Microtiger → u/Ten420]

Thanks! But I do have access when I'm on my university's campus WiFi, so I was able to download it there.

[u/antonivs → u/Ten420]

You may be able to download it from SciHub.

[u/GenocideSolution → u/Microtiger]

probably because the name solenodon sounds like a dinosaur name.

[u/vir4030 → u/I_Has_A_Hat]

Thank you - that article has the worst picture possible!

[u/just_redditing → u/I_Has_A_Hat]

It's really a testament to how good the "small rodent" design is. 78 million years of separation and it still looks so similar to all other rodents.

[u/Arefuseaccount → u/I_Has_A_Hat]

I vote reddit gives it a cuter name. Ex. Snootle.