Praying mantis seen hunting for fish in wild for first time | Hacker News Reader

Praying mantis seen hunting for fish in wild for first time

independent.co.uk

104 pointsHillaryBriss57 comments

> mantises appear to have evolved impressive learning abilities too

I found a mid-sized mantis on my porch the other day. These things are fascinating. It seemed to have genuine curiosity. I kinda waved my hand in front of it, and its gaze followed for a bit before it seemed to get bored with my hand and then looked me straight in the eyes. Then it casually walked away without breaking its gaze (its head turning nearly 180 degrees as it walked the other way). I'm sure I was projecting and it was just trying to avoid being eaten, but it seemed way more intelligent than other insects.

Thankfully these things aren't dangerous to humans otherwise I'm sure they'd have us enslaved by now.

> Thankfully these things aren't dangerous to humans otherwise I'm sure they'd have us enslaved by now.

There's still hope. We may get discovered by a warlike spacefaring species.

If history has taught us anything, it's that we are the most likely to enslave ourselves.

Yes, some intergalactic conflict against a hostile alien species would be welcome if it meant getting a breaking from fighting over the same old shit between ourselves.

We did that to most mammals alive today.

There's a curious and slightly creepy effect when you look into the eyes of a mantis (or other creature with the same kind of eyes, like certain species of shrimp), and dark "pupils" seem to be staring directly at you. Those aren't real pupils, however, but pseudopupils -- an optical effect where you happen to be looking at a straight line into one of the facets that make up the compound eyes. Seen head on, the ommatidia appear dark or black, while the surrounding ommatidia reflect the light outwards.

> I'm sure I was projecting and it was just trying to avoid being eaten, but it seemed way more intelligent than other insects.

Really interesting, but I agree it's most likely just a projection.

Possibly due to the fact that mantises are the only insect (that I can think of at least) that indicates focus by turning its head toward something?

The power of human emotional projection is extremely strong. I had the misfortune of seeing domesticated dogs in great distress (to put it mildly) a few times when I was younger, and one thing I always remember is that while experiencing the distress, the dogs would still make that familiar panting facial expression that most people innately perceive as a dog "smiling" or expressing happiness/joy.

As a result I have a very different experience from most people when I observe the behavior of dogs. I haven't seen any behavior in dogs yet that are any indication to me that they're capable of experiencing happiness/joy.

I'm somewhat convinced that people's perception of the emotional spectrum of dogs in particular is almost entirely an optimistic human construct. Their behavior patterns and how they appear to experience things actually seems extremely narrow to me, roughly the same as most other animals. I think the one exception to that is that dogs are unique in their tendency to adapt those behaviors in a domestic environment as though dogs and humans were members of the same species.

I grew up on a farm and I have seen animals free from human interaction display playfulness, happiness, fear, pain and anger - Dogs, horses, cattle, sheep. In all cases I found these behaviours unambiguous and demonstrating a relatively rich inner life, that I find not at all unexpected from their neurobiology

That’s a very Cartesian world view on biology, luckily abandoned a long time ago. Animals where merely automatons and scientists dissecting dogs alive could gleefully ignore their cries as nothing more than automatic response stimuli. Today we know that physiologically humans are not very different from other mammals, even if we want to be. We all have a limbic system and that means we all have the same emotions. Animals have feelings and emotions. When things happen to them, they react with emotions be it sorrow, anger, happiness, fear.

What other animals have a limbic system. Are some species' more developed than others or are the base components the same in every species that has one?

Carl Segan at the end of The Demon haunted World talks extensively about this mechanistic worldview, where animals were once thought of as clockwork.

I’d just note that your comment reads a bit like I endorse this view - whereas the intention of my post was to refute it. Perhaps you meant to reply to my parent?

Yes, sorry. I managed to click on the wrong link in the HN iOS app.

What you’re claiming of the comment you replied to is the complete opposite of what it states.

Exactly. The op is essentially agreeing with the gp, but seems to be saying that the op’s view was ‘luckily abandoned a long time ago.’

I think mammals have pretty much the same set of emotions that we do. Insects, probably not.

> It seemed to have genuine curiosity.

Yeah, they really do. I found one on a sidewalk a while back. Watched it for a while, then it came right up to me. I got it to come onto my hand. No fear.

Last picture here:

http://justinpombrio.net/about-me/pictures/

I left it in some bamboo after.

a small one! In japanese mountains I have come across specimens that are at least 25 cm long. Bigger than one s hand. Truly terrifying!

> it seemed way more intelligent than other insects.

Pretty sure most predators are more intelligent than their prey.

I got in a fist fight with one of those little guys once.

He really wanted something of mine, he kept picking it up and walking away with it and I would swipe it out of his hands and put it back.

Finally he just got flat out pissed and started snapping at me, rearing back in a fighting stance and jabbing at me any time I came near. He went from super chill to super mean in an instant

I've encountered a few mantes before but that one takes the cake. They are SO SMART!

That's wonderful and terrifying. How much 'damage' did it do when it jabbed/snapped at you? Enough to draw blood or hurt for a while?

I'm always a bit fearful to pick them up (more so after reading this article - they can kill birds!).

It's amazing how such a tiny thing can strike fear into people as large as us. It just felt like a hard pinch. But the ferocity with which he would strike made me recoil every time. And the hiss. Such a fascinating display of character for an insect.

Does anyone know of other insects as expressive as mantes?

https://youtu.be/ooZtzyHTX7g

Maybe first time in the wild, bit we've known they eat fish for a long time. The above is a video of one catching and eating a fish, posted to YouTube 10 years ago.

Disturbing that it does not kill its prey first.

Insects tend to be like that; they just start eating.

Often though they tend to target the head or neck for their first bites, I think with the intent that biting there will make the meal stop struggling[1]. Not all the time though, sometimes they grab the prey and just start chowing down, butt first :P

[1] I had an African flower mantis as a pet ;)

How'd your mantis do with human interaction? I've been fascinated with them since I met one outside a couple weeks ago. They seem like they could do some real damage if they wanted to but all the reading I've done it seems like they're pretty tolerant of being handled and rarely/never bite.

> They seem like they could do some real damage if they wanted to

A mantis could do real damage to a human?

I have had this memory from some time ago about a scene from a podcast. Scientists in a lab are trying to wrangle an insect (which I remember to be a mantis of some kind) with a glass rod. The insect bites the rod with such force that it snaps and the arc of the motion lacerates the bugs middle (thorax?). From the cut fat begins to come out. Instictually the bug begins to eat it's own fat while dying.

I wish I could remember or find the podcast. I feel like it was radio lab, but can't find it.

https://www.wnycstudios.org/story/185551-killer-empathy/

The largest species can draw blood and might if they thought your wiggling finger were a flying insect. I don't know of any cases where a mantis did "real damage" to a human.

Some can be quite shy, but generally they are content to be handled and carried. They are a lot of fun as a pet.

Mine was in captivity since a child, so I don't think it ever developed the skills to fly. But sometimes when I would handle it, it would open and reveal it's eye-spotted wings; maybe because it thought I was a threat, or maybe just to impress me :P. When it was close to dying, it's behavior became erratic and it would fall over and not really be in control of itself. It did clamp onto my finger and take some nibbles in its near death state of confusion, but the spines nor bites could Pierce the skin. I barely felt it.

TL;DR = mine handled fine and possibly enjoyed the excitement of adventuring up my arm. Never any naughty behavior until senility set in.

They don't learn to fly, they just have that ability after their wings are developed. It's just that they don't fly often (in captivity or the wild).

Also, my experience with the order in which they eat their prey is different from yours. Mine would eat fruit flies ass-first and would tear the wings off moths, both while the prey were alive.

> [1] I had an African flower mantis as a pet ;)

types—this—into—google—images What the..! This kind (flower mantices) really looks incredible!

Clicky: https://www.google.com/search?tbm=isch&q=African+flower+mant...

It's not like it had sex with it before or anything /s

It's a lot more common in the wild than one thinks. Lions, tigers, wild dogs, alligators, fish, sharks, baboons, birds, hyenas, worms, bears, etc all eat animals that are still alive from time to time. Animals want to conserve as much enery as they can. As long as the prey is debilitated or not attracting other bigger predators, they'll eat it even if it is alive. Nature is really brutal when you get down to it.

So do humans.

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

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

Yes, and it is noted in the article: Praying mantises have occasionally been observed to feed on vertebrates, including small birds, lizards, frogs, newts, mice, snakes and turtles.

But many of these cases have either not been scientifically validated or have occurred under human-manipulated circumstances. And there is no previous scientific data of mantises preying on fish.

I don't understand what they mean for it to be "scientifically observed".

I wonder what reaction the authors would get if the paper they submitted was entirely based on watching Youtube?

I think the "preying on fish" part is key here not "scientifically observed." A captive mantis eating a fish placed in front of it is different from a wild mantis specifically hunting fish.

Perhaps merely “in a reproducable fashion”.

Well, the youtube video clearly"occurred under human-manipulated circumstances".

That probably just means observed by a scientist. If I report seeing a praying mantis eat a fish, that's not as reliable as if I have a video or if a trained scientist makes the same report.

Why doesn't the fish wriggle? The fish looks much stronger than the insect.

What's the idiom... Like being nudged towards eating fish in a barrel.

I'm fascinated by the choice of soundtrack on this video.

I love the last sentence of the article:

> Adult females are known to eat their mating partners after sex.

Just thought they'd throw that one in before signing off! But I do suppose a writer would be remiss not to remind you of that fact given the opportunity.

And a fascinating comment (which I haven't confirmed yet) from a reader below the article:

> Sigh, females HAVE to eat the head of the male to remove the inhibition stopping him from climaxing. > > It doesn't happen AFTER sex, it is required for the sex to be successful in terms of conception.

I never knew that. This behavior has only ever been explained to me as some kind of vindictive or inexplicable act by the female mantis.

I wonder how the female mantis knows that this is a way to disinhibit the male's climax?? Nature can be so strange.

If this is true, she doesn't have to know why she's doing it. If there's a genetic variation that causes this behavior and enough of an advantage to doing it, that's what natural selection will favor.

Still controversial: https://news.ycombinator.com/item?id=18049366

That's wrong, they don't have to do it. But it sure does help if they're not otherwise getting enough to eat!

https://en.wikipedia.org/wiki/Mantis#Sexual_cannibalism

Apparently it happens more often under laboratory conditions than in the wild.

> Early researchers thought that because copulatory movement is controlled by a ganglion in the abdomen, not the head, removal of the male's head was a reproductive strategy by females to enhance fertilization while obtaining sustenance. Later, this behavior appeared to be an artifact of intrusive laboratory observation. Whether the behavior is natural in the field or also the result of distractions caused by the human observer remains controversial.

Pullout game so strong that females have to turn you into a vegetable to make sure you impregnate them

Source: https://jor.pensoft.net/articles.php?id=28067

> The research team were surprised by the visual capability of the mantis, which could see its prey underneath the surface of the water.

According to this 2010 video[0] of a mantis catching a goldfish, the mantis has no problem doing this, however it was a human-manipulated situation during daylight.

[0] https://www.youtube.com/watch?v=ooZtzyHTX7g

shouldn't the title be "preying"?

> "[Their] upright posture, while remaining stationary with forearms folded, has led to the common name praying mantis."

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

Reply on news.ycombinator.com