There is much about 2018 that will make me relieved to see it receding in the distance behind me. Partly as a consequence I’ve taken the easy way out with this end-of-year post, devoting it to a couple of random bits of natural history miscellany. Still, this exercise has prompted me to think that it might be helpful in the new year to try a different perspective on things in general.
Sneaky Sex
Psychologist David P. Barash penned a wonderful line in a recent piece (Survival of the Sneakiest, The New York Times, December 15, 2018):
At equilibrium, the evolutionary race is not only to the big and aggressive, but also to a certain number of the small and sneaky.Barash observes that the common understanding that the largest and fiercest animals are the ones who always win the race, whether it be to capture prey or mate, ignores the support that natural selection can give to creatures who come up with alternative strategies that sometimes dupe the alphas of the group. Further, investing too much in those robust or attractive features that lead to competitive success can have deleterious effects. Examples of this are many. For instance, Barash writes about “aggressive neglect” among bird species that are so intent on warding off trespassers that they fail to fulfill their duties to their young. Or, on a very, very small scale, a recent study of the microscopic fossil shells of ostracodes, my favorite crustaceans, showed a correlation between investment in a very large copulatory apparatus and a greatly increased chance of an ostracode species going extinct. (Ed Yong, When a Bigger Penis Means Swifter Extinction, The Atlantic, April 11, 2018.)
But it’s those individuals who manage to do an end-around the clearly dominant ones in order to get their genes reproduced that Barash focuses on. Again, the examples of these alternative strategies are numerous. For instance, male pumpkinseed sunfish, he notes, are typically aggressive, large, and colorful, vigorously defending their territories and their mates. Some males, though, benefit from a devious strategy that has managed to evolve. They mimic female sunfish in color and size and, once welcomed into a male’s territory, wait for the opportune moment to impregnate the real females’ eggs. The University of California Museum of Paleontology’s Understanding Evolution website has a superb post on these alternative, devious strategies. Titled Evolution’s Dating and Mating Game (May, 2008), it opens with a description of the involved drama over mating for an Indonesian octopus species. This is marked by fighting to guard a chosen female, but also punctuated by the strategy of female impersonation by smaller, male octopuses. Lest one think that mimicking females is the go-to alternative, the Museum’s post lists, and I quote, the following examples of other strategies:
• Sly male crickets produce no chirp themselves, but poach females attracted to another cricket's call.These two broad strategies – consider them boldness versus sneakiness – are in competition, ebbing and flowing in a population as an evolutionary equilibrium is sought.
• Sneaker squid get love on the run by zipping up to a couple that has recently mated, rapidly depositing sperm in the female (in a quick, six-second affair!), and taking off again.
• Sneaky sand gobies hide in the sediment near a couple's nest, waiting for an opportunity to slip into the nest to fertilize a few eggs on the sly before getting chased out by the resident male.
• Small dung beetles play the milkman calling at the back door. They excavate a side entrance into the tunnel system guarded by a larger dominant beetle, mate with the female chambered there, and try to slip away undetected.
• The smallest males of one marine isopod species make up for their small size with heavy investment in sperm. These little crustaceans sneak into the sponge commandeered as a love nest by a larger male and then dive bomb the mating couple, releasing a cloud of sperm at the critical moment.
My takeaway is nothing profound and perhaps a stretch, but offers some solace: when it looks like the deck is stacked against me, there may well be a way.
Geology and Fossils Everywhere
We build with stone and such quarried stone tells stories of its geological origins. With my limited knowledge of geology, they aren’t stories I can read on my own. But, on occasion, I stumble on a knowledgeable and enthusiastic guide. I’m a bit better with the fossils that might be found in building stone. I’ve posted before on the exciting adventure that is urban fossiling and remain on the lookout for good material related to it (some links are listed in the column at the right of this post). I was quite taken by two recent pieces about the tales to be gleaned from stone.
How could I resist the post titled Bathroom Geology that appeared earlier this year (October 25 2018) on the blog Time Scavengers? Written by Jen Bauer, a postdoc at the Florida Museum of Natural History, the post focuses on the geology behind the stone found in five different bathrooms. She opens with a granite counter top in a Richmond, Virginia, restaurant’s restroom, exploring how the large size of some of the crystals in the material helps explain the fluctuating temperatures at which the magma cooled. She then segues to the granite found in the bathroom of a private home, said granite missing the large crystals of the previous example but being replete with tiny almandine garnets (seems there was a great deal of aluminum in this magma). She’s then on to the geology behind the impressive example of migmatite found in a ladies' room at the San Francisco airport. Skipping her next stop for the moment, she wraps up with the bathroom at her mother’s house. Its counter features labradorite which forms, not in granite such as that of the initial stalls covered in her post, but in something with an explosive history like basalt.
Her fourth pit stop was at a public bathroom in St. Petersburg, Florida. The walls of this facility are rich with fossils. Bauer posits that fossil shells in this stone are from Florida and are roughly 10-20 million years. I would quibble a bit with her on this because, since she doesn’t explore the geology behind the stone used in these walls, it’s not clear how she can be sure that this limestone (what it certainly is) was, in fact, quarried locally. Regardless, fossils in a bathroom are always a treat.
All in all, a nice tour of five lavatories.
I suspect geologist Sidney Horenstein, who died in early December, would have enjoyed the restroom tour. Subject of a nice obituary (Sam Roberts, Sidney Horenstein, 82, Geologist Who Wrung Stories From Stone, Dies, The New York Times, December 10, 2018), Horenstein was one of those favored few who can commune with deep time. His bailiwick was New York City, and his muse the bedrock upon which the city is built and which shows through in some places, as well as the stone with which the city is built.
His obituary features a quick tour of a few of the geologic and fossil treasures that abound in New York City. Stops mentioned include Saks Fifth Avenue (coral fossils in the doorway), Brooklyn Municipal Building (brachiopods), Comcast Building in Rockefeller Center (fossil snail in the limestone lobby), and the Western Union Building (fossil clams). Though he clearly enjoyed finding fossils in building stone, he gave the geology of New York City its due, seeing evidence in the rock around him of events ranging from mountain building to glaciers sliding over the land that came to support the city. The gusto with which he embraced the city’s geology is abundantly evident when he was described by writer William J. Broad (How the Ice Age Shaped New York City, The New York Times, June 5, 2018):
Talkative and outgoing, his shirt often untucked, the model of a rumpled geologist, Mr. Horenstein is a native New Yorker with boyish enthusiasm for the city’s hidden faults and early beginnings, for ancient blows and catastrophes. A compendium of geologic jokes, he refers to himself not as a raconteur but a rockconteur.As for the attraction of reading the geologic world around him, Broad quotes Horenstein as saying, “It keeps me young. . . . There’s always something to see, something you missed, something new.”
It’s an affirming perspective on aspects of life, not just things geologic, and one I intend to take into the new year.
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