Readers’ wildlife photos, purloined edition. (Or: “You won’t believe this stunning mantis!”)

January 10, 2016 • 8:00 am

Instead of presenting our own readers’ photographs, I wanted today to highlight a post by naturalist/evolutionist/photographer Piotr Naskrecki from his wonderful website The Smaller Majority.  I doubt that Piotr reads my site, so he probably doesn’t qualify as a “reader,” but I do know him and have permission to reproduce his photos. That’s good enough for me, for today’s post, in which I shamelessly steal his photos and descriptions, will stun you with yet another achievement of natural selection.

In fact, the species at hand, the ghost mantis Phyloocrania paradoxais a fantastic example of crypsis (camouflage). The resemblance of this species to a leaf is simply amazing—involving shape, color, and behavior. As Wikipedia notes:

Phyllocrania paradoxa is camouflaged so as to appear as dead, dried-up leaf material. It has an elongated head, a flattened, extended prothorax (together referred to as its “elaborate headdress and shoulder shields” by one enthusiast), and leaf-like protrusions from its limbs. The mantis also has a forewing that looks like a desiccated leaf,  and the “creases” in the wings are actually shadings of pigment.

Wikipedia says that the genus Phyloocrania contains three species, but Naskrecki says that they’ve all been “synonymized” (lumped into a single species). The confusion comes because there’s tremendous polymorphism (variation among individuals) in both shape and color, so dividing individuals up into species, particularly for populations living in different places, is tricky at best. And the reason for this variation, which I’ll discuss in a second, is unclear.

The best photos and description can be seen at Piotr’s new post, “Ghost hunting.” First, a photo (all captions are by Piotr, and photos are copyrighted). Look at this thing! Can you even tell front from back?

A female ghost mantis (Phyllocrania paradoxa) – these insects are such superb mimics of dry vegetation that it is often difficult to tell which part belongs to the plant and which to the insect.

After first learning about this remarkable creature, Piotr went to Zimbabwe, with the mantis high on his bucket list. He had trouble finding one but finally succeeded:

The ghost mantis was one of my most desired quarries and I started looking for it the moment I landed. Alas, a month on and with no trace of the animal, it was beginning to feel as if I were really hunting a ghost. I had spent countless hours sifting through the leaf litter, scanning bushes and trees, sweeping my net through all kinds of vegetation – nothing.

One day I stood on the platform of a railway station, waiting for a train to take me to Bulawayo. It was late October, the peak of the dry season, and shriveled leaves were falling from trees onto my head in a rare, merciful breeze. One, fairly large and twisted brown leaf landed on my shoulder. I tried to brush it off but it just sat there, trembling in the wind. I flicked it again. It landed lower on my sleeve. And then the leaf started to climb up my arm. I looked, still not believing. Could it be? No, this is just a piece of withered plant. But it was, finally, a ghost mantis.

They come in a variety of colors, with the color changing at each molt. Here are two different-colored specimens (note the differences in shape as well):

No two individuals of ghost mantids are alike, which prevents their principal predators, birds and primates, from learning how to tell them apart from real leaves.

It took Naskrecki 25 years before he saw another one of these, this time in Mozambique’s Gorongosa National Park, where he’s been spending a lot of time. He notes that ghost mantids are widely available to collectors:

Thanks to their otherworldly appearance ghost mantids have long been the favorite of amateur insect collectors and, since they can be easily bred in captivity, they have recently become very popular in the pet trade. Now all you need to do to see a live ghost mantis is to pay a few bucks online and one will be delivered to your door. But for an animal so widely kept, shockingly little is known about its biology and behavior in its natural habitat.

The polymorphism for color, which appears to rest on changes at each molt, immediately raised a question for Matthew and me. If the color makes the mantid cryptic on leaves, and the color must match the leaves, how does the mantid know what color it is? It must have a way of matching its color to its background, so it has to know what color it is. Can it see itself, or does it have some endogenous way, not involving self-inspection, to “know” what color it is and choose an appropriate background? Or does it even go to the appropriate background? (After all, perhaps you can be a brown mantid on a green tree and still enjoy some protection from predators.)

It is probably to the mantis’s advantage to change color with molts. That way, as Naskrecki suggests in the photo caption above, the predator has a harder time learning to pick you out from the environment, as it has to learn various colors. (This form of selection, in which the rarer types are favored because it’s harder for the predator to learn their color or pattern, is called “negative frequency-dependent selection”.) Or perhaps not—if the predator hunts by shape alone.

And why is shape so variable? (There’s an example of this in the third photograph below.) Such variation among individuals in morphology is remarkable in insects; I know of no other species in which individuals differ from each other so strikingly. That, too, could be an adaptation: a developmental program that is sufficiently plastic to allow the cuticles of different individuals to develop in different ways. (I find this less likely than variation in color.) But there’s a constraint: they still must always resemble leaves. How much variation is there among individuals? And do individuals change their “ornamentation” with each molt?

I’ve raised many questions here, but none have answers. The question of whether an individual can choose a matching background should be easily answerable in the lab: just put individuals in cages where they have a choice of vegetation. So far as I know, that hasn’t been done, but even a hobbyist could do that, and get a scientific paper!

An alternative hypothesis: if an individual molts on a certain vegetation, perhaps its developmental program will channel its color into that of the background vegetation. If the mantis tends to stay put on that vegetation, it need not be forced to “choose” a background that matches its color. I’ve described an example of such developmental polymorphism in an earlier post on the moth caterpillar Nemoria arizonaria, so it’s possible that this also occurs with the mantid. But that presumes that mantids stay put. And we don’t know whether they do.

Finally, if they’re so bloody cryptic, how does a male find a female when it’s mating time? Piotr suggests that they use pheromones. That’s a reasonable hypothesis, but again, we just don’t know. There’s a lot of interesting work to be done on this species!

Here’s a female ghost mantis with a newly-laid ootheca (egg case): the white structure behind it:


There’s more information (and more photographs) at Piotr’s site, so go over and have a look (be sure to see the photo of a mantis molting). We’ll end with two more of Piotr’s lovely photos:

A silhouette of the first ghost mantis (Phyllocrania paradoxa) recorded from Gorongosa National Park in Mozambique.

This photo shows the variation in both color and morphology.


Now you surely want to see some videos, and, because this species is commercially available, there are many on YouTube. I’ll show three.

As Piotr says, this species is an “ambush predator”: individuals wait until some hapless insect walks or flies within range, and then quickly strike. Here’s a video of a captive mantis taking down a waxworm (at 45 sec. in; note the speed of the strike and how the mantis holds its front legs up by its head):

Here’s a brown female being handled:

And here’s a green morph:

Note that Naskrecki also has a photo-and-science book with the same name as his website, a book that got great reviews as well as a rare starred review from Publishers Weekly. It was published in 2007 by Harvard University Press, and would make a nice present for lovers of nature photography and biology.

Finally, I’d love to have one of these mantids (I won’t, though, as it’s a bit of trouble and I travel a lot), and since they’re bred in captivity that doesn’t endanger the wild populations. There are many places to buy them (one is here), but be sure you learn how to take care of them properly (go here).

h/t: Matthew Cobb

Spot the hidden animals: 20 opportunities!

October 27, 2015 • 3:21 pm

Well, if you’re not very good at playing “spot the nightjar” on this site, here’s a chance to spot 20 animals, and it’s not too hard. At you’ll find 20 photos of animals that you can scrutinize sequentially, and when you click on the “forward” arrow, the animal is circled so you can see if you were right.

Go try your luck. Here are four teasers.

Spot the leopard. (Yes, it’s already spotted. . . )

Spot the impala.


Spot the wolf.


Spot the willow ptarmigan.

Willow Ptarmigan

I bet you got them all!

h/t: Ant

Orchid mantis: does it really mimic an orchid?

March 9, 2015 • 9:45 am

I believe I’ve posted several times about the “orchid mantis,” a term for a variety of mantises that mimic—or appear to mimic—orchids. These mantids are believed to sit among flowers, and resemble the flower so strongly that pollinators like bees try to pollinate them. But instead of getting pollen, the bee gets snapped up by the mantid when they fly into its arms. Here are a few of the mantids showing their resemblance to flowers:




Below is an Attenborough video showing the mantis deceiving a bush cricket, who loses its life. It also shows another cool fact: this species is not mimetic as a juvenile, but aposematic: it has “warning coloration” showing that it’s toxic. For some reason, perhaps connected with the mantis’s increasing size, it changes shape and color as it ages, changing from conspicuous to cryptic.

This is a classic example of “aggressive mimicry,” so called because the purported evolutionary pressure was to get food (through aggression) rather than simply to hide form predators. But, like many cases of mimicry, the “pollinator-deceiving” mimicry is inferred, and hasn’t been scientifically tested. To do that you’d have to experiment on these species (and they’re not easy to come by), showing that pollinators do indeed mistake the mantis for an orchid flower. And to test another hypothesis—that the mantis gains additional camouflage by hiding among the orchids it’s said to resemble—you’d have to show that the mantis gets more prey when it’s sitting among flowers than when sitting alone. That hadn’t been done either.

Further, there’s an alternative hypothesis: that the mantid isn’t camouflaged to deceive prey, but to deceive predators. After all, the aposematic coloration of the juvenile above probably evolved to warn away predators who have learned to avoid the toxicity associated with that coloration. And that implies that something tries to eat these creatures. Finally, the flower-resemblance of the adult could serve to simultaneously deceive both predators and prey.

To test these hypotheses, James O’Hanlon, Gregory Holwell, and Marie Herberstein, a group of researchers from Australia and New Zealand, did experimental tests on insects and flowers in Malaysia. The results appear in the two papers at bottom (with links). What they found is that the conventional wisdom is correct in some respects, but the story is more complicated.  I’ll just summarize the main findings. Tests were done on a single species of tropical flower mantid: Hymenopus coronatus.  Here’s a photo of a subadult female from the American Naturalist paper:

Screen Shot 2015-03-09 at 8.53.15 AMHere are the salient results:

  • Yes, the mantids do mimic flowers, but not necessarily a particular orchid. This conclusion comes from color-spectrum analysis of the insects and flowers filtered through what a pollinator (a bee) really sees. This shows that the mantid resembles the colors of a number of local flowers, but the authors weren’t able to find a specific orchid that the tested mantis resembled. (Note: they didn’t look all that hard.) But given their ability to find mantids sitting around on many flowers besides orchids, and even on vegetation, it’s likely that the mantis evolved to resemble a generalized flower rather than a given species of orchid. This makes more sense because a given species of orchid is not ubiquitous in the rain forests, and they flower irregularly.
  • Tests in which the researchers observed pollinators “inspecting” (deviating from a flight path to come closer to an object) a control object (a stick), a common species of flower in the area tied to a stick, and a mantid tethered to a stick showed that pollinators barely visited the stick, visited the flower moderately often, but visited the mantid most often (in fact, several instances of predation were observed).  This shows that the mantid by iteself is even more attractive than the flower, so it’s not simply hiding itself among flowers  to enhance its resemblance to a flower.
  • However, mantis sitting next to flowers got a higher rate of pollinator inspection than did solitary mantises, and the higher the density of flowers around a mantis, the more the mantis was “inspected”—and presumably the more noms it got. Therefore, although mantids can attract pollinators on their own, this ability is enhanced when they’re sitting amongst a bunch of flowers. Because solitary mantises seem more attractive to pollinators than are solitary flowers (implying that the mantids don’t have to hide to deceive the insect), this result probably reflects the fact that a patch of flowers simply draws more insects than do solitary flowers.
  • The authors tested, using a Y-tube, whether the mantids chose to go to flowers more often than to leaves, which would imply a form of habitat selection. They found no effect: mantids went down the “leaf” arm of the Y as often as down the “flower arm”.  So, though it may be adaptive for a mantid to be drawn to a group of flowers (because it gets more prey), that behavior hasn’t evolved. But a Y-tube test may not be the best way to test habitat selection, as it’s an extremely artificial situation.

So the conventional wisdom confirmed here is that the mantids do resemble flowers, fool predators that way, and can get noms by their resemblance. The conventional wisdom that was overturned is that these mantids resemble orchids, or a specific species of orchid. Also, the results don’t support the notion that the mimicry is imperfect, so that the mantids must hide among flowers to get any prey. They do get more prey when hiding among flowers, but that’s because more pollinators are attracted to large groups of flowers. Finally, the authors found no support for the idea that mantids seek out the flowers and hide among them. Because that behavior would seem adaptive, I’d like to see better tests, tests using, say, a large cage with flowers and leaves instead of a simple Y-tube choice experiment.

But, of course, lots of work remains. Did the authors miss an orchid that the mantis really resembles? Does the mimicry protect the insect from predation in addition to helping it find prey? Are there other cues that attract insects besides the color and shape of the mantis? It is possible, after all, that the insect has evolved pheromones, or a scent, that also attracts pollinators. Remember that the case of orchids that mimic insects to get pollinated (the reverse situation; deceived bees try to copulate with bee-mimicking orchids and, in the process, get pollen stuck to their bodies), those orchids have evolved a scent that mimics bee pheromones.

Finally, the photos above show that far more than color is involved in this mimicry. The mantids have developed elaborate petal-like extensions to their legs and bodies, as well as special markings, that also mimic flowers. The authors tested only color resemblance, but clearly the mantid also mimics the shape of flowers. It’s likely that a pollinator will be attracted to the general vicinity of the mantid by its color (bees don’t see that well!), and then make a final decision to approach more closely based on shape. That would impose strong selection on the mantids to look more like flowers.

h/t:Matthew Cobb



O’Hanlon, J. C.M.E. Herbersteinand G.I. Holwell. 2014. Habitat selection in a deceptive predator: maximizing resource availability and signal efficacy. Behavioral Ecology, online, doi: 10.1093/beheco/aru179.

O’Hanlon, J. C., Gregory I. Holwell, and Marie E. Herberstein. Pollinator Deception in the Orchid MantisThe American Naturalist, Vol. 183, No. 1 (January 2014), pp. 126-132

The remarkable spider-tailed viper

February 18, 2015 • 6:57 am

I’ve previously written a post on the spider-tailed viper (Pseudocerastes urarachnoides), a wonderful snake that has a bizarre and deceptively spider-like appendage on its tail.  It was discovered in 1968 in Iran, but described as a new species only in 2006, with the authors speculating that the appendage could be used to lure prey.  Below is a picture of the snake’s “caudal appendage” taken from the well-named website Life is short, but snakes are long (LISBSAL), which also describes the developmental basis of this structure:

. . . the structure of the [appendage], which is formed of the last pair of subcaudal scales, much enlarged, and a single enlarged dorsal scale. The elongated components are modified lateral scales. X-rays taken by the team showed that the caudal vertebrae extend well into this structure and are not deformed or modified.

Screen Shot 2015-02-18 at 6.34.40 AM

So what we have here, as we nearly always do with new structures in evolution, is simply the modification of an old structure in a novel way. One could imagine that mutations that affected the rear scales, making them bigger and more spidery-looking, could give a reproductive advantage (more food!) to the mutant snake. Further mutations would make the lure even more spider-like and more attractive to prey. And perhaps the tail-waving was already in place, though it was surely elaborated after this structure began to evolve.

As I noted in my earlier post, this appendage could function to scare off predators, but the way the snake waves the appendage suggests that it’s a deceptive lure to attract prey who thinks they’re going to eat a juicy spider. Here’s a video of lure-waving:

Further, the informative post on LISBAL on “Spider-tailed adders” gives other information suggesting that this is indeed an evolved trait helping the snake capture prey, particularly birds:

Behavioral observations made in 2008 of a live P. urarachnoides captured in western Iran and maintained in captivity confirm these ideas. Closed-circuit video was used to record behavior, and the results published in the Russian Journal of Herpetology by Behzad Fathinia of Razi University and his colleagues. They observed the snake, a juvenile male that regurgitated a Crested Lark, using its caudal lure to attract sparrows and baby chickens that they introduced into its enclosure. When the birds approached and pecked the tail, the snake struck and envenomated the birds, a process taking less than one half second. A bird was also found in the stomach of the paratype specimen, further evidence that this species might feed heavily on birds in the wild with the aid of its spectacular caudal lure. The tail of P. urarachnoides probably represents the most elaborate morphological caudal ornamentation known in any snake, with the possible exception of the sound-producing rattles of rattlesnakes.

And, indeed, the video below, which came out a year after my first post, shows how the spider “lure” can attract a bird, which is then killed. This video is a bit heavy on rhetoric and light on science, but it still shows the effectiveness of the deceptive tail.

h/t: Mathieu


Readers’ wildlife photos

January 19, 2015 • 6:55 am

Jacques Hausser sent pictures of hoverflies (syrphids) as well as  his identifications. Hoverflies, in the family Syrphidae, are true flies—that is, they’re members of the insect order Diptera. Syrphids feed on nectar and pollen, and are thus sometimes called “flower flies.” Many of these harmless flies, like the four below, are Batesian mimics of more dangerous insects: bees or wasps in the order Hymenoptera (those having four wings rather than the flies’ two), probably because both frequent the same areas. The hoverflies are clearly evolved to deceive predators.  Jacques’ captions and notes are indented.

Volucella zonaria – obviously trying to mimic a hornet [JAC: I’m not sure what those red sacs are attached to the thorax; you can also see them in the fourth photo.]


Helophilus pendulus:


Xanthogramma pedissequum:


Chrysotoxum bicinctus:


And reader Christi sent this photo of a rattlesnake (species unknown, but not for long, I suspect), lying cryptically in the leaves. Watch where you step!




Readers’ wildlife photographs

January 11, 2015 • 6:08 am

Reader Rodger in Thailand sent a picture from his garden, showing the chrysalis (cocoon) of either a moth or butterfly on one of his plants. Can you spot it? Pretty cryptic, no? It’s clearly evolved (in both morphology and position) to resemble a leaf in this most vulnerable of life stages. If anyone can identify it, please do so.


Reader Tony Eales sent these way back in October, which shows you that I have a reserve (but please top up the tank by sending me your good wildlife photos NOW):

Just came back from a trip to World Heritage Fraser Island National Park. The sandy soil, wetland, heath, known in the local indigenous language as the Wallum, dominates the island and it’s my favourite ecosystem in the world. The plants of the Wallum heath fascinate me with beautiful carnivorous plants like sundews (Drosera spatulatapictured) and bladderworts (Utricularia lateriflora pictured…I think).

Here’s the sundew:


While I photographed plenty of birds it was the other wildlife that really caught my eye. I saw large Peacock Carpenter Bees (Xylocopa bombylans) feeding on Melastoma affine. And I finally got a decent photo of the striking Tiger Moth (Amata sp.).

Again, can anyone identify the species?


There were quite a few reptiles. I photographed a small lace monitor (Varanus varius) in the rain forest and played “spot the…” with Major Skinks (Bellatorias frerei).


And I also got to see the most famous charismatic megafauna of the region, Humpback Whales (Megaptera novaeangliae):




The conehead mantis

November 24, 2014 • 2:45 pm

I had no idea this creature existed, so it’s a bit of a thrill to see it for the first time. The photo below shows two specimens of the conehead mantis, Empusa pennata, endemic to southern Europe and Turkey. This lovely photograph is from Project Noah. The blobs on the branch are part of the plant, not the insect’s legs. But the insect still looks like part of the branch.

Screen shot 2014-11-23 at 6.53.13 PM

Here are two more photos of coneheads, the first from CosmosThis surely could be a model for a nefarious Alien-like space creature:

Pboto:: Veer Images

Do you suppose it consumes mass quantities of insects?

And another, from Trek Nature, showing the variability in color. The page adds this (notice the Latin name for the European praying mantis):

This species of mantis, although similar in size to the common European Praying mantis (Mantis religiosa), is easily distinguished by the protrusion from its crown. Both male and females, even from first hatching carry this tall extension giving them a very alien appearance. They live in areas that are warm and dry and use their cryptic colouring of either greens and pinks or various shades of brown to keep them hidden from predators. The female may grow to a length of 10cm while the male is shorter and slimmer. The male has distinctive ‘feather’ type antennae as shown on the image above.

Photo by Mehmet Karababa (taken in Turkey)

There are several videos of this creature on YouTube; all show it moving erratically, which may be a form of crypsis, mimicking a branch blown by irregular winds. That was one theory, which was mine, but then I remembered that some chameleons move erratically in that way as well. Perhaps readers have some suggestions; I’m sure there’s discussion about this movement in the scientific literature.

Here’s the Finnish mammal

September 14, 2014 • 9:35 am

by Matthew Cobb

Sophie Scott’s mystery mammal she spotted in a Finnish birch forest was, as many either saw or guessed, an elk, which was hiding behind a tree in the background of her photo. Elk is another name for moose (and vice versa) – their Latin name is Alces alces, and they are the largest extant member of the deer family.

They are not the same species or even genus as caribou/reindeer (Rangifer tarandus), which are also large deer, but which do not have the distinctive palmate antlers of the moose/elk.


The most famous elk is the extinct Giant Irish Elk, which used to roam across much of northern Europe before disappearing as the ice retreated and our ancestors moved north to hunt. Other explanations of their extinction are available (I know, we posted this a couple of years back):


We are lucky enough to have an Irish Elk skull and antlers on display in the foyer of the Michael Smith Building where I work at the University of Manchester. This cartoon appears on the explanatory panel along with some more serious scientific data.

Pika-boo: here’s the lagomorph

August 25, 2014 • 1:08 pm

Earlier today I posted reader Jeremy’s photo of a pika, both in close-up and then in the distance in its rocky environs.  I looked at it for the longest time, even in the enlarged photo like the first one below, and couldn’t find the damn thing. Then I finally spotted it; it’s almost as hard as a nightjar.

I’ll put the original photo up first (click to enlarge it even more if you still want to look for the pika), and then a photo with the pika circled, sent by Jeremy (he called it “pika-boo”!).  Hint: if you look at the original, the beast is just to the right of center:






The reveal:

Pika boo (1)

And an enlarged view:

Screen Shot 2014-08-25 at 10.38.34 AM