We have two readers contributing today. First, Mark Sturtevant sent an email headed “Picture of HUGE INSECTS,” and indeed it was!
His notes:
Here is a picture of some Cecropia moth larvae that I had raised a few years back. The Cecropia moth (Hyalophora cecropia) is the largest native moth in North America, with wing spans up to 6 inches. It belongs to the family Saturniidae, which is the family of giant silk moths that include other familiar species (Luna moths, Polyphemus moths, etc.). I am sorry to say I have no pictures of the adults that came from these monster larvae, although I had a lot of the moths flying around the house about 8 months later. I am working to rectify that as I am now raising another batch of cecropias, and am documenting the process with lots of pictures.
Sorry that this picture is a bit out of focus. The cecropia larvae were not happy with being off of their food plant, and they were crawling around frantically. That is a lot of insect weight, btw!
How did I get these? One can purchase eggs and pupae (for cheap) of pretty much anyNorth American species of Saturniids from a person named Bill Oehlke. He maintains a web site here. I have no affiliation there, btw. The site also contains instructions for rearing, food, etc. It is very easy and fun to raise Saturniids, as the food plants for most species are very common. I raise Cecropias from our lilac bush, but they will accept over a dozen other common species of tree or shrub.
And a few photos from Sarah Crews. Sarah’s a biologist, and her notes (indented) reflect what a biologist needs to know about each species!
Columbian ground squirrel (Urocitellus columbianus), the species I mistakenly called a prairie dog last week.
Yoho NP, BC
Desert harvestman (Eurybunus sp.):
Rosy boa and its leg “spurs.” Those “spurs” are actually the vestigial legs of the snake, which, like all snakes, evolved from four-legged “lizardlike” creatures which were not the ancestors of modern lizards. If you dissect them, you’ll see that the spurs have other bones homologous to the leg and pelvic bones of four-footed land creatrues (tetrapods). I’ve put a skeleton at the bottom. This constitutes evidence for evolution, as the spurs are of no use to the snake. Further, in some early fossil snakes you can see that the legs are larger than these spurs, and were almost certainly in the process of disappearing.
Lichanura orcutti – Anza Borrego Desert SP
Photo and caption below from caving.uk.co:
“Legless lizards” are true lizards that have either lost their legs completely or have similar vestigial limbs, but they are not in the same group as snakes, though both descended from four-legged ancestors. In some species the legs are more developed than those of the rosy boa above, but are still clearly useless, and perhaps on the way out. For pictures of legless lizards, go here.
Finally, again from Sarah, a snake fly:
Snake Fly: Order: Raphidoptera: Fam: Raphidiidae, Agulla. sp. – used to be Neuroptera – all the neuropteroids are really cool – esp. the juvenile stages – CA: Lake Co., Kelseyville
Interesting info and great photos in all but the Cecropia won my heart: such beauties! With their aquamarine colouring elegantly studded with gold, they could be trained to act like live bracelets. 🙂
Most of the Saturniids are decorated with colorful studs or spines (most are safe to handle, btw). The Cecropias are one of my favorites because they change their colors dramatically as they grow. The 1st instar larvae are black, and the 2nd instars are bright yellow. They change to this blue-green color during the 3rd instar.
You’re lucky they all matured into adults 8 months later; a book I read on them said that researchers in Illinois, where they are plentiful, assumed at first that the eggs laid one year would all reach adulthood the next- they came to find out that most did, but some stayed in the pupa form for 2 years, some for 5, and some for as long as 7! Nature’s way of “hedging her bets”, should a catastrophe wipe out their food sources?
Woa. I certainly did not know about that! I have a batch of hickory horned devil pupae from last year that still will not come out. Maybe I need to keep them.
Very pretty. Thanks for sharing. Interestingly, sometimes harvestmen – opiliones – have small red ticks which suck at them on the body or by leg joints.
Interesting, the vesigial remains of pelvis and legs of the Indian python. One wonders why the Almighty did not remove these parts completely when he banned the snake from the Garden of Eden. Does the snake have any power of speech remaining?
And funny how they are right where the ribs transition to just spine — just with other tetrapods. 🙂
Hey jerry, i found an excellent website devoted to the evidence of evolution. You might want to check it out and link it to your readers.. Tons of interesting pictures of remnants and a whole lot more.
http://www.evolutionevidence.org/evidence/remnants/
Yes, that’s very nice. I wish I had it when I wrote my book; I could have purchased some of those illustrations. Thanks.
Wow those are great photos. Those giant Cecropia larvae look fun! They would be juicy eating for the birds here though unless they taste really bad – they look like they would taste really bad.
I’ve never seen a snake insect before. It looks very strange – like a snake had was just plunked on its body.
The prairie dog is so cute. I loved seeing them in Alberta – they often have that “wah?” look on their faces.
The snake shot with the wide open lens is very pretty – they have the loveliest eyes (along with frogs and toads).
This isn’t a prairie dog; but the effect is the same! 🙂
Ha! Yeah I saw that one on QI once.
I am not sure how they taste (to birds or humans). Another species known as hickory horned devils might taste bad, as they give off a mild odor when annoyed.
Ha, that is funny. My reaction was that they look like they would taste good!
[I prefer my hexapodans juvenile but the rest of the edible crustaceans adult. So sue my palate.]
Yeah, I know, the white fat larvae is the innocent ones. But adding colors on the plate would be nice, now when insects is pushed as the next affordable meat.
..I think I will look into buying some moth eggs because there are few things in this world I enjoy more than a handful of giant caterpillars. Maybe Wooly Bear eggs.
I do not think those are sold at this site. If you want to try your hand at this rewarding hobby but want to start with an especially ‘easy’ species, I recommend starting with Luna moths.
The link above is for cocoons. Here is a more general link for eggs and general rearing info. Eggs, etc..
I raise my critters indoors, in transparent boxes and jars with bouquets of leaves. They give you something to putter around with every day, but reward you by getting really big. Kids go bonkers over these things.
I did this for a few years. The really neat thing with cecropias is if you get your moths to overwinter (they do so as pupae) and if one that emerges the next spring/summer is a female, you can put her in a screen cage outside (or in your house against an open window) and she will attract wild males… it is the most glorious thing to have several huge moths silently and fearlessly flying around you in pre-dawn hours. Once she mates she stops emitting pheromone so keeping her behind bars for a few hours may bring in quite a few males.
be sure to let some go though… wild populations in many areas are suffering due to too much lighting attracting the moths and disrupting mating (also, bats get to them before they mate)
I wasn’t clear a the end there…what I meant, when I said be sure to let some go, is that you can let some of the stock you raise go and do their own thing in nature, —but I was thinking that because in my case I had found a wild, local female pupa that started things off for me. I raised them for three years, and kept some for pinning and display, but I always let some go too.
I am not so sure I would let some go if I had purchased them from another location, tho… not sure if that would mess up local gene pools or what.
I do not know of a problem with messing with the local gene pool. With wild populations low, adding a few outsiders might alleviate a little of their inbreeding.
I would not release non-native species, however. Although I very much doubt that these insects would become a pest anywhere, it is a matter of principle.
“I would not release non-native species, however.”
Indeed. That is what I’d like any reader here to take away from my having brought the subject up.
I worked on a govt. gypsy moth project in the U.S. for a few years. Talk about invasive species! Anyone reading this who thinks it might be okay to release any non-native species should do a little reading on that one!
I live in an apartment and don’t have a balcony, so if I buy some eggs I’d take the adults to one of the wooded areas and let them go boost the local population. I know there’s several kinds of giant silkworm around, but you rarely ever see them.
Sarah, I have a question about this statement: “Those ‘spurs’ are actually the vestigial legs of the snake, which, like all snakes, evolved from four-legged ‘lizardlike’ creatures which were not the ancestors of modern lizards.”
That sent me scurrying off to look into squamate phylogenies. The most recent tree I could find was the one by Wiens, et al, who used nuclear DNA studies across virtually all the families of squmates, and who published in 2012. Their tree places the Serpentes as the sister group to the lineage that leads to such ‘modern’ taxa as Varanidae, Agamidae, Iguanidae, and the like. Don’t those count as modern lizards, and wouldn’t they share common ancestry with the snakes?
Am I misreading the data? Are there problems with their data and/or analysis?
I think that you’re right. Modern phylogenies have Serpentes embedded among modern lizard taxa. Mind you, a hard-core cladist would say that the common ancestor of lizards and snakes is neither a lizard nor a snake.
That’s what I thought, Lars. But the way she phrased the statement was that snakes “evolved from four-legged ‘lizardlike’ creatures which were not the ancestors of modern lizards.”
That’s what bothered me. According to recent phylogenies, snakes are the sister group to a lineage that leads to several–though not all–families of lizards, and that certainly implies common ancestry for both snakes and some lizards. I wondered if those families of lizards that comprise the snakes’ sister group were not considered ‘modern’ lizards for some reason.
There is a school of thought among some systematists which holds that a common ancestor of two groups can’t be held to belong to either; this could be behind the “lizardlike creature” usage, as the common ancestor of both lizards and snakes could not be considered to be either a lizard or a snake.
I’ve always found this to be a bit excessive. Especially, as you point out, that snakes share a common ancestor with some lizards that they don’t share with others.
Systematic terminology can be a bit of a bugger sometimes.
Yes, that’s why I said that: to avoid the wrath of cladists!
To be avoided at all costs. At least, that’s the way it was back in the 80s. A caustic bunch.
“…evolved from four-legged “lizardlike” creatures which were not the ancestors of modern lizards.”
I don’t know what that was supposed to mean. It seems to be a claim that snakes and lizards never had a common ancestor that was lizardlike. Or never had common ancestry at all? Anyway, that’s contrary to all the evidence.
If snakes are the sister group to Anguimorpha and/or Iguania* (lizards), and Scincomorpha and Gekkota (also lizards) branched off further down the stem, then snakes ARE lizards. The last common ancestor of ALL lizards would be an early lizard; one might make it the ‘first’ lizard by definition (that’d be a good way to define Squamata).
Very few ‘cladistic’ papers have ever claimed support for a ‘lizard’ clade excluding snakes; there was one in the early 1980s that tried to resolve a three-taxon cladogram of Serpentes (snakes), Sauria (‘lizards’) and Amphisbaenia, which of course made the unwarranted assumption that they were each monophyletic.
*Since a wonderfully modern phylogenetic study of lizards done in 1923 (!) up until less than a decade ago, iguanians were considered the most primitive and probably basal branch of squamates. DNA puts them about as close to snakes as snakes are to anguimorphans, which is highly inconsistent with the morphological evidence. Very curious.
I see you’ve read Camp.
If the author was being very careful about distinguishing stem clades from crown clades, she might have thought that the common ancestor of two crown clades (lizards and snakes) couldn’t be identified as belonging to either, even if they were lizards for all intents and purposes.
On the other hand, perhaps I shouldn’t be trying to read her mind.
Great photos today! I love it when the Reader’s Wildlife Photos have background information like these. Feel like I’m in a classroom again. Thanks!
The Rosy boa head is just too cool. Like Diane said, the most stunning eyes, and capturing the flick of the tongue. Yay!
And Mark, those caterpillars are amazing. Can’t wait for you to post photos of their continuing growth and metamorphosis…assuming you do, that is. Would love to see their adult selves as well as the cocoon and pupa.
Thanks! And we will maybe see….
Pelvic spurs are of no use for locomotion, but in several species of Pythons the males use them to stimulate the female during mating. Lots of male snakes will rub or vibrate their body on top of the female while mating so this is probably an example of vestigial organs getting co-opted into another use.
That’s a good point; I didn’t know they were used for anything. Of course creationists claim that if a vestigial organ is used for anything, it can’t be evidence for evolution, but that’s simply wrong, for it’s clear from the morphology of these bones that they come from ancestral pelvises and legs. The penguin has vestigial wings, for instance, and is descended from flying birds, but its vestigial wings clearly have uses, swimming being the most important.