Today we have photos from regular Mark Sturtevant. His notes and IDs are indented, and you can enlarge the photos by clicking on them. I’ll remind readers to send in your good photos, as we’re running low.
Mark:
Here are some pictures of mainly arthropods, taken in 2021 as the weather began to finally warm near my habitat in eastern Michigan.
An early opportunity was a European paper wasp (Polistes dominula) that emerged from hibernation on the front porch. It was still quite cold, so she was motionless most of the time. After a long winter, I was glad to see her even though the species is invasive and problematic in the U.S. because it has reduced populations of the native paper wasps. These pictures are focus stacked from about 100 pictures each, taken with the assistance of a Helicon Fb tube. That is a device that lets you do rapid focus bracketing with a DSLR camera.
Next is a ground spider (Gnaphosidae), a family of free roaming spiders that include some ant mimics. This is Zelotes fratris. This too is focus stacked, but from a few pictures taken by hand. Note the red velvet mite photo bomb.
Here is a very young green frog (Lithobates clamitans), only recently transformed from a tadpole. Often mistaken for the closely related bullfrog, green frogs can be identified by the dorso-lateral ridge that you can see here. This youngster may one day grow to be the size of both of your fists put together.
The big event for the early part of the 2021 season was a possibly once-in-a-lifetime chance to photograph 17-year cicadas, Magicicada septendecim. Cicadas spend most of their lives as nymphs living underground, where they feed on sap from tree roots. “Periodical” cicadas include a 13-year species and the 17-year species. After those many years, the nymphs emerge en masse in biblical plague numbers, mate, lay eggs, and die over a period of several weeks. It is believed their reproduction cycle evolved to overwhelm predators who cannot grow their population in response. The 2021 season was due to have “Brood X” of the 17-year cicadas, which is the largest population of this species. Brood X extends over multiple states in the US, and one edge of this group extends into southern Michigan. So, with the help of the internet, which provided records about their last emergence, I made the long drive to a likely park to see this marvel. The trip was well rewarded with high thousands of cicadas.
Here are various pictures showing perching cicadas, and a bush with quite a few of them. Cicadas were flying everywhere, and collisions with them were pretty frequent. Males are especially distinct with their bright red eyes.
The eerie sound of thousands of cicadas filled the air over the field. But it was evident that there were far more of them in the trees that surrounded the park, since the trees were fairly deafening with their shrill, spooky music. Accounts from other areas of the Brood X emergence described even heavier population densities, where pretty much everything gets covered by them.
It’s the males who sing, and they do so by forcing air past a stack of vibrating membranes under a pair of “tymbal” plates on the abdomen. This picture showing the plates is blurry because the male was continually squalling in protest.
Here is a wide angle macro picture of a cicada posing with my good friend Gary Miller. Gary is an excellent macro photographer in his own right. It was not even summer, and this is one of my favorite pictures of the entire season.
I wanted to find a video that conveys what this natural wonder is like. This amateur recording is a very good match to what the emergence was like in this field, right down to the screaming trees in the distance:
Readers in the eastern U.S. may have direct experience with seeing a periodical cicada mass emergence, and if you’d like to make plans for seeing one, here is a map that can get people started.
Thank you for looking!
Oh cool, I was wondering about cicada life cycles and _region_ – so apparently, it really is uniform – so not 17 years in area 1 overlapping with 17 years in area 2. Thanks I’ll check that map!
…. or perhaps no! The years are all off by 1, so it is all overlap depending on _brood_. Fascinating….
Beautiful photos, as always. I’m always amazed by how brilliantly bright the eyes of the cicadas are. They look almost artificial.
Mark Sturtevant thank you for the images and the enlightening commentary. I must know if you are using a tripod or a helper in the shot where you are in the background.
Thank you. I don’t use a tripod (that being too cumbersome and slow to set up). I was likely using a monopod to help me with the picture of my friend. The monopod is not attached to the camera, however. Instead, I use a monopod “V-yoke” (on Amazon) to rest the lens on. This is much faster to set up but it also stabilizes well enough.
All accessories for shooting are to solve a need, but they also introduce new problems. A V-yoke and the monopod offers fast set up, and it takes the weight of the camera while stabilizing it. But it is not rock solid like a tripod would be.
Brood X is composed of three 17-year cicada species: Magicicada septendecim, M. septendecula, and M. cassini. When they emerged here in the mid-Atlantic, I was able to identify members of all three species, though M. septendecim were by far the most common. The three species look very similar to each other, but can be distinguished primarily by the yellow stripes on the abdomen (as in Mark’s photo). M. septendecim has wide stripes, M. septendecula has narrow stripes, and M. cassini has no stripes at all. The three species also make different sounds. Mark’s excellent pictures look like all M. septendecim to me.
An excellent point! Thank you.
The cicadas in my area, suburb south of Chicago seem to have declined steadily since the the 1950’s; and in the last few years, around here, there’s always as small population emerging each year, as if they’re on the wrong calendar system.
How did evolution decide to have 13yr and 17yr cycles anyway? Was there one group that split off into two groups? When did science notice they were two distinct groups?
There are 13 and 17 year cicadas, prime numbers, and I gather they are different species (which would probably answer your last question). It is reputed there are 7 year cicadas too (although I could not find any actual data there), but no 11 year, 19 year or 23 year cicadas. I also gather that not all cicada species are periodical. One reason you can hear cicadas every year. I also gather there are different populations with different 13/17 year cycles. I guess that would defeat the prime numbers evolution.
It is thought -albeit not universally- that these prime number cycles have to do with predator avoidance, or rather predator satiation. First of all 13 and 17 year cycles would only coincide once in more than 200 years, which is notable in itself.
https://www.nature.com/articles/news010726-3
[Nice trivia: the ‘prime number sieve’ designed by Eratosthenes, but preceded by the cicada ‘sieve’, was indeed the same guy (well, genius) who calculated the circumference of the Earth within about a thousand km or so, well before our era (about 200 BC).]
I think there is still a lot more to be said and discovered about cicada cycles, why, for example, you can evolve from a 13 year evolutionary success to a 17 year one, that would imply intermediate stages of 14, 15 and horrid 16 (divisible by 2,4 and 8, 3 cycles) years. Or was there a ‘lucky jump’? A regulatory gene gone rogue?
The two observed cicada life cycles are either 13 and 17 years.
13 is the 6th prime number.
17 is the 7th prime number.
… 13 and 17 are odd.
… what does this mean besides some observed life cycles can be even or odd?
That is, how is it not a mistake that 13 and 17 are prime?
Hasty searching has not turned up a clear explanation for me. I can see they modeled the cicada – have any others been subjected to that test?
So the null hypothesis – that it is unimportant that 13 and 17 are prime – seems not to be rejected (based on my ignorant position).
Apparently the 13 and 17 year life cycles have evolved on 8 separate occasions in the last 4 million years (Wikipedia). It is intriguing that the strategy does not seem to have evolved in cicadas anywhere else or in other groups.
Cicadas and frogs are amazing! Paper wasps? They’d rather sting you than look at you. The coloring says it all.
Thank you for the pictures!
There are 3 distinct species of 17-year cicadas, that emerge in synchrony, and 3 corresponding species of 13-year cicadas, further south. Chris Simon, at University of Connecticut, has done much of the research on them. The emergences are indeed spectacular.
Huh – Can you say which broods on the map are which of the species?
That’d be interesting if there’s a discernible pattern .
Great post! Great photos and video. Very eerie critters.
Thanks!
Great cicada shots! Back in 2013 I caught the emergence of Brood 2 in Princeton NJ. I thought it would be cool to measure their oxygen consumption while singing, and with that in mind some students and I caught about 50 of them. Brought them back to the lab (in Trenton) in triumph, set them up in terraria with sticks to perch on.
Next morning all were dead.
That was a great wide-angle macro of the cicada and your friend- neat perspective. The other photos were excellent as well- thanks for all the coolness.
Wondrous. I think the frog has to be my favourite of this set, and I’m surprised by how armoured the spider looks.
Mark, what kind of wide macro lens is it, please?
good question…I’m also curious.
Great pics. the Zelotes is interesting. i’ve photographed them in Australia as well, probably Z. sarawakensis or an undescribed Australian species. Seems they all look the same and I guess the distribution or examination of genitals or DNa would be the only real way to tell one species from another.
This is kinda long but worth it I think – it is intriguing! :
There are cicadas, and then there are the 13-or-17-year ones I had previously not understood to be a kind of separate beast (if I may use the expression):
https://en.m.wikipedia.org/wiki/Periodical_cicadas
There are two hypotheses for the peculiar life cycle, and I quote :
“On this prime number hypothesis, a predator with a three-year reproductive cycle, which happened to coincide with a brood emergence in a given year, will have gone through either four cycles plus one year (12 + 1) or five cycles plus two years (15 + 2) by the next time that brood emerges. […] they nearly always emerge when some portion of the predators they will confront are sexually immature and therefore incapable of taking maximum advantage of the momentarily limitless food supply.[23]”
ref. 23 is the Goles, et. al. Complexity paper cited above (albeit as a Nature News and Views).
And the second “… posits that the prime-numbered developmental times represent an adaptation to prevent hybridization between broods. ”
… more citations in there.
I hopethe italics worked.Also see the counterpart to periodic cicada :
https://en.m.wikipedia.org/wiki/Annual_cicada
… the map shows only periodic cicadas, I guess. And not Brood XX.
Excellent photos as always! I really like the young green frog image – very cinematic.
Beautiful photos Mark! Thanks!