About twenty years ago I read a book called “The Ghosts of Evolution” by Connie Barlow. It discussed evolutionary anachronisms, plant characteristics which no longer make sense because the plant species is missing a partner for which the characteristic evolved. Specifically, the book referenced several trees with large fruits which no longer have an appropriate animal partner to eat the fruits and disperse the seed. The book is based upon an influential paper written in 1982 by Dan Janzen and Paul Martin (of Pleistocene overkill fame) about fruits found in Mesoamerican forests. The evocative title was backed up by an interesting book I would like to read again.

At about the same time as I read the book we were renting a small native grass pasture and stocking it with a few horses. After renting it for several years I noticed several prairie turnips (Pediomelum esculentum) growing in low moist ground by the gate. Seed dispersal for prairie turnips is accomplished by tumbling; when the plants mature they form an abscission layer at ground level, break off, and tumble across the prairie dropping seeds as they go. I am confident these seeds did not get to the gate by tumbling. The nearest turnips were over a quarter of a mile away with two sloughs in between. My money is on the horses, who spent a lot of time near the gate.

I realize that the establishment of those turnips was probably a fluke. Prairie turnips are not normally found in such wet areas. Still, it made quite an impression on me. While I can’t identify anachronistic characteristics in prairie turnips – they tumble around quite well – there are almost inevitably other plants that had fruits made to induce bison or elk or perhaps even the horses that roamed our continent until 10-15,000 years ago, to eat and disperse their seed.

One plant I wonder about in this regard is groundplum, or buffalobean milkvetch (Astragalus crassicarpus). Are their seedpods an evolutionary anachronism? The pods do not seem to be consumed by any animal other than me, with year old pods often still around when the plant is developing new fruit. Having me eat them is a waste of the plants energy because I eat them long before seeds are mature while they are still tender and sweet, making me a crappy seed disperser – pun intended. It is confusing that they seem best to eat when seeds are immature; most fruits are tastiest at maturity when seeds are ready to germinate. At maturity buffalobeans are locked away in a tough seed casing. Perhaps the partner they are missing is a rodent; a ground squirrel who caches them and perhaps fails to eat all of them. Buffalobean milkvetch is common, at least in my neighborhood, so I am probably missing something. Still it seems a waste to see the year old pods all dressed up with no place to go.

As I have written before, one impetus for my project was the discovery of Dakota skipper butterflies (Hesperae dacotae) on my nearby prairie. Not only mammals have been and are being lost as reproductive partners. Most of my land qualified for the CRP program as pollinator habitat. The money for pollinator habitat restoration has been driven by worries about honeybees and monarch butterflies. I doubt there would have been much demand for restoring pollinator habitat if the symbols were the Dakota skipper butterfly and native bees. A small irony is that my prairie restoration is partially supported by “colony collapse” disorder of honeybees, a non-native species I would prefer not to have by my restoration to compete with native bees.

To get back on track, I wonder how many native prairie species are missing, or have an insufficient number of pollinators. Pollinator relationships are not necessarily exclusive and many plants can be pollinated by wind-borne pollen, or self-pollinate. Truly efficient pollination however, may require a specific partner species. Could 100 acres of restored prairie indirectly improve the fitness of native prairie species in a larger landscape?

If there were prairie species that had an exclusive pollination relationship with an extinct pollinator we might never know. They are gone. The very existence of the plants we see implies that any partners that are essential still exist. Still, there is obviously a middle ground or the phrase “evolutionary anachronism” would never have been coined. There may be species just hanging on with diminished populations because of a lack of pollinators or seed dispersers. I doubt there is a robust research literature for all the native prairie species whose seeds I gather. Even in an area with a lot of native grasslands such as where I grew up, it is impossible to walk around without feeling the presence of ghosts.

I always circle back to the value of my prairie restoration beyond that of a “vanity project”. What ecosystem services will it provide? As much as I love prairie, I also love farming. My career’s work is helping farmers to raise crops more efficiently while improving their land. Some of the land that is in the restoration, perhaps 40 acres, is productive farm ground and I struggle with whether those acres should have been included in the restoration. I have mentioned the Dakota skipper several times, but I would like to determine what other benefits might accrue past helping one species. Might this project extend habitats for local plant genotypes that I am gathering seed from? Might it help pollinator species that could go on to help native plant species in the larger landscape? And if I add in carbon sequestration and water quality improvement, does this start to add up to something significant? I’m writing this post (and I do actually write every post longhand, at least two written drafts before it is typed) during a February blizzard and I have a bad case of cabin fever. While I am not exactly in an existential crisis, I am questioning all my assumptions. Why am I doing what I am doing? What grassland birds will be able to use my restoration? What insects nearby could use a larger territory to establish a population? Hell, what soil microorganisms in my neighborhood are looking for a new place to stretch their metaphorical legs? What future “ghosts of evolution” can I provide succor to? Blizzard dreams; I may as well dream big.