To many, February may bring to mind valentines and chocolate, groundhogs and presidents. That is, unless you're a science nerd and were counting the days until Charles Darwin's birthday.
Charles Darwin, the father of evolutionary theory was born on February 12, 1809, making this year the 208th anniversary of his birth. Biologists around the world celebrate Darwin as the co-originator of the fundamental pillar of modern biology. Museums, as storehouses of the diversity of life on Earth, are particularly indebted to Darwin's observant and iconoclastic mind.
I heard that within our collection of roughly one million entomology specimens—insects and spiders—we have an insect that was collected by Darwin himself. Entomology contains some of the Museum’s more beautiful and bizarre specimens. To many people, our spiders and stinging or blood sucking insects are the stuff of nightmares. However, the collection is also home to exquisitely colored and patterned animals, both fascinating and strange. Open any drawer and amazing stories leap out, especially if you have an entomologist like Michael Wall at your side.
Few people would be wowed by a drawer of brown lacewings (family Hemerobiidae). They're small, dun colored, and different from each other in ways only a lacewing mother or entomologist would appreciate.
Lacewings may look innocuous, but according to Dr. Wall they are actually vicious if you are a fellow insect. Voracious predators, they mostly eat aphids and other soft-bodied insects. We have a large collection of local lacewings, but Darwin's specimen is kept separately in a case with other rare or special holdings.
We occasionally trade specimens with other museums, especially if we have a surplus of a particular species. It appears that Darwin’s brown lacewing arrived as part of a trade about two decades ago, and it is likely that nobody noticed who collected it from “Hobart Town” until Michael’s predecessor, a lacewing expert, pored over the new accessions. One has to look carefully at the tiny tag to see “C. Darwin.”
Fittingly for theNAT, Darwin started as a citizen scientist. He embraced the British beetle collecting craze in the 1820s, publishing entomology articles while studying theology at Christ’s College, Cambridge. The letter inviting him to join the voyage of the HMS Beagle—Darwin's formative experience from December 1831 to October 1836—emphasized that the self-funded position was most appropriate for a “gentleman.”
Our humble brown lacewing collected in Hobart, on the island of Tasmania, in February 1863 would have come from Darwin's voyage on the Beagle. He likely collected it by beating a shrub with a net. The young naturalist would have placed it in a kill jar and then, like most other field biologists, worked at night to prepare the specimen. Darwin would have gingerly placed a tiny pin through the thorax just behind the head. He would have noted the location and date on a small card and stored the specimen in a safe place. After the voyage many of Darwin’s insect specimens were sent to Oxford University.
Although Darwin’s lacewing specimen is locked safely away, evidence of evolution is abundant throughout our Museum. Michael and I took a walk through the Fossil Mysteries exhibition with paleontologist Tom Deméré to see a fossil link between cats and dogs.
Tapocyon robustus roamed San Diego County 42 million years ago. The amazingly intact specimen on display was found by Brad Riney in Oceanside, California. Tapocyon is considered a “stem carnivoran,” or the early part of the branch of animals that includes today's mammalian carnivorans (e.g., cats, hyenas, dogs, bears, etc.). The fossil preserves a mosaic of characteristics found today only in cats ("felids"), and others that are found only in dogs ("canids"). This makes Tapocyon a prehistoric “cat-dog.” Tapocyon had retractable claws, an early adaptation for climbing that also facilitated in grabbing prey. This feature combined with forearm bones that allowed Tapocyon to rotate its paws toward and away from the body, are found in today’s cats. In addition, Tapocyon had blade-like cheek teeth with crowns to shear meat, much like a modern cat's teeth. However, the skull reveals a set of crushing back teeth that cats lack, and are found in living dogs.
If you're out on the exhibit floor you can take your own tour of the marvels of evolution in Fossil Mysteries. Be sure to see the predatory ungulates, early meat-eating relatives of pigs, cows, deer, and elephants. We welcome your visit, but there is no need to go to a museum to see evolution in action. All of life on earth is a product of evolution, including chocolate, groundhogs, and presidents.
Michael Wall in Entomology collections storage with a drawer of brown lacewings from San Diego.
Paleontologist Tom Deméré with the rest of the Tapocyon specimen in our collections storage.
An artist’s rendition of Tapocyon, in Oceanside 42 million years ago.
Tapocyon skull shows cat-like shearing teeth and dog-like crushing teeth.
Posted by President and CEO Judy Gradwohl on February 15, 2017
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