"What a thousand acres of Silphiums looked like when they tickled the bellies of the buffalo is a question never again to be answered, and perhaps not even asked." -Aldo Leopold
Part of the Horn’s Prairie Grove LWR with obedient plant blooming in the foreground and joe pye weed behind.
The WGNSS Entomology and Nature Photography Groups had a splendid treat in July of 2022 when we jointly visited Horn’s Prairie Grove Land Water Reserve (LWR) near Ramsey IL. This 40 acre patch represents part of the less than 1% of the remaining southern till plain prairie ecosystem that was nearly wiped from the planet due to land conversion for farming. Even better, about 30 acres are original “virgin” prairie, (the largest intact remnant prairie in IL) meaning these spots were never touched by the plow. Even better still, at this location there lies five different types of prairie habitat: seep/wetland, dry hillside, mesic, black soil and savanna.
Keith Horn, owner and guide to Horn’s Prairie Grove LWR
The story of this land is interesting. The current owners, Keith and Patty Horn, purchased the land in 2001 as “junk land” from an old farmer who’s family had owned since the 1870s. They liked the fact that the majority of the land was in a “wild” state. The untouched 30 acres had been used as a wild hay field, being cut almost yearly. They had noticed some nice wildflowers in bloom but did not realize what they had until a few years into a wildlife habitat improvement plan that included periodic burning. Every year they noticed more and more species in bloom. They have sought help in identifying the plant species here and the current list is now at 619 species, including six native orchid species! Bravo to the Horns for identifying what they had and taking the steps to see their land improved. This remnant prairie could have been destroyed in the blink of an eye if it had fallen into the wrong hands.
Although most of us were simply thrilled to be in such high quality habitat, the primary purpose of the trip was to check out the arthropod life. Unfortunately, in late July, we were there on a truly miserable day of weather. The heat and humidity created a heat index that was well above the safety zone. This meant not many of us had the nerve to do a great deal of walking and searching, especially much after lunch time.
Efferia aestuans, the friendly robber (Family Asilidae)
Calopteryx maculata, an ebony jewelwing damselfly that was found on the forest and prairie edge.
Members of our group walking among the blooming Liatris.
A gorgeous Poanes zabulon, Zabulon skipper (Family Hesperiidae)
What I am calling Wallengrenia egeremet, the northern broken-dash (Family Hesperiidae)
Keith Horn (back) and Chris Brown (front)
We were lucky to find both Mydas fly species to be found in Illinois, but I was only able to photograph this Mydas tibialis.
The gnat ogre! (Holcocephala sp.)
Interested in making visits to interesting high-quality habitats like this? Then consider joining Webster Groves Nature Study Society! Visit http://www.wgnss.org to find out more.
Dicerca pugionata (Buprestidae) photographed at Victoria Glades Conservation Area, Jefferson County, MO.
Many thanks to Ted MacRae for introducing me to another stunner of a beetle. On more than one occasion Ted has taken me and others out to the field to find one of the strikingly beautiful and rare beetles that he knows so well. This time the treasure we sought was the jewel beetle, Dicerca pugionata (Buprestidae), also known as the Witch-hazel Borer. Witch-hazels (Hamamelis spp.) may be the preferred host plant but they are also found on alders (Alnus spp.) and ninebark (Physocarpus opulifolius). In this opportunity, we went to a specific patch of ninebark at Victoria Glades where Ted had found them previously.
Dicerca pugionata (Buprestidae) on its host plant, ninebark (Physocarpus opulifolius)
I finally got to spend some time at Roaring River C.A. this past spring when Casey and I made a trip to the southwest of the state. This location is easily seen driving to and from Roaring River State Park. At this time, the Castilleja coccinea (Indian paintbrush) and Camassia scilloides (wild hyacinth) were the stars of the show, accenting the hilly glades and savannahs.
Castilleja coccinea (Indian paintbrush) in bloom at Roaring River Conservation Area.
A sepia treatment was given to this infra-red capture of the savannah at Roaring River Conservation Area.
For the past few years I have noticed a good number of native bee nest holes along exposed sections of bare soil at one of my favorite hiking and nature observation sites – August G. Beckemeier Conservation Area in St. Louis Co., MO. This past spring I finally decided to make this a project and set about a quest to make some images of these gals provisioning their nests. As usual, I wound up learning along the way.
An Agapostemon virescens pauses at the entrance of the largest of the communal nest entrances I observed. It is impossible for me to accurately count the number of females using this ~ 10 cm tall conical entrance, but I observed six individuals at one time on or hovering above the entrance.
As is commonly known, many of our native bees are solitary and nest without close contact or cooperation in regards to conspecifics. At the opposite side of this spectrum of sociality in the Hymenoptera are most species of bumble bees and the honeybee. These bees are considered truly social, or, eusocial. The characteristics necessary to be considered a eusocial species are 1) cooperative care of offspring of others within the colony, 2) overlapping generations within a colony of adults, and 3) a division of labor into reproductive and non-reproductive groups. Many of our bee species lie somewhere between these two extremes. The bee of focus here, Agapostemon virescens, lies early in the area we call being presocial, aka parasocial.
Two Agapostemon virescens females exiting a communal nest entrance having dropped off their loads into their individual cells.
Let’s clarify the differences between a presocial species such as A. virescens and the eusocial honeybee. The honeybee shows all three necessary characteristics of a eusocial species. The individual workers obviously care for brood that are not their own – they don’t even have offspring of their own, instead spending much of their lives caring for the offspring of their queen (sisters). They have multiple overlapping generations within the hive in a particular season, as well as across multiple seasons and as just mentioned, there is a division of labor into reproductive and non-reproductive castes.A. virescens on the other hand, is not nearly as cooperative. Individuals of this species share basically just a front door to their brood chambers and nothing more. After entering the communal nest, each female builds their own brood sub-chamber cells and each provisions their own by processing pollen into cakes and leaving them in their respective brood chambers. There is no brood care after the egg is deposited and the sub-chamber sealed. The offspring then emerges later in the summer.
So, what are the pre-conditions necessary for the eventual development of more complicated forms of sociality, i.e. eusociality? Or more directly, what advantages are there in adopting more of a social lifestyle if we assume the starting point was a solitary existence? Scientists consider two important pre-conditions need be met for the evolution of eusociality. First, the species offspring must be altricial, or require a great amount of parental care in order to reach maturity. Second, there need be low reproductive success rates of solitary pairs that attempt to reproduce. Here is what is believed to be the primary driver that pushed A. virescens into this presocial condition.
A sentry Agapostemon virescens stands guard at the communal nest entrance allowing only conspecifics to enter. This guarding of potential kleptoparastism is regarded as the primary benefit that led to communal nesting in this species.
This sentry Agapostemon virescens closely inspects an incoming conspecific. How it is determined who stands watch while its neighbors forage is not known.
Kleptoparasitism is where one animal takes advantage of the hard work of another by taking their prey or collected foods. In this case, we are primarily concerned with the large group of bees known as cuckoo bees. Kleptoparasitism has evolved numerous times in the Hymenoptera and cuckoo bees lay their egg on or near the host’s provisions. The parasite will hatch first and eat the host’s pollen and will often kill and eat the host’s larvae as well. With such an obviously successful reproductive strategy, it should come as no surprise that there would be a strong selective advantage of finding ways to thwart these parasites. In the case of A. virescens, evidence suggests that by communal living as described here, the rate of kleptoparasitism is much lower when compared to related species that have the completely solitary reproductive strategy.
A busy day of bringing in pollen provisions for these Agapostemon virescens sweat bees.
I guess the obvious next question is how in the world could eusociality evolve from this state? This is a fascinating story that involves terms like kin selection, altruism and haplodiploidy. It also involves a good deal of math and explanation from some of the greatest evolutionary thinkers since the time of Darwin (read anything by William D. Hamilton for example). It is also well out of the scope of this piece. But, I hope it is clear that before getting near the high rung of eusociality on this ladder, that a small first step like seen in this example would be necessary.
Although Agapostemon virescens sweat bees are communal nesters, this photo gives a clue that they are not cooperative foragers like the honeybee. Each of the three returning females is carrying different colored pollen, indicating different pollen source plants for each.
I hope I got most of this correct enough. It’s been a long time since I took Zuleyma Tang-Martinez’s Evolution of Animal Sociality class at University, which I thoroughly enjoyed. Please feel free to leave a comment to correct or clarify or ask a question.
Much of what I covered here and a lot more can be found in Malte Andersson’s The evolution of eusociality (Ann. Rev. Ecol. Syst. 1984. 15:165-89
I finally had a good chance to photograph these spectacular flowers at peak bloom. Photographed at Don Robinson State Park, Jefferson County, MO on 28, Aug, 2021.
Trichostema dichotomum (forked bluecurls) are members of the mint family (Lamiaceae).
Trichostema dichotomum (forked bluecurls) seem to make for great garden plants. I hope to get some seeds to try in the front beds.
Echinacea paradoxa, also known as Ozark coneflower, Bush’s coneflower and yellow coneflower is found natively in southwestern Missouri, Arkansas and Oklahoma. I was happy to see this one flowered during its first year in my front yard garden.
A Thousand Acres of Silphiums 