Sunday, January 17, 2016

Premature Delivery

Laney and the zebra swallowtail - Chris Barnhart
Similar to the annual first baby born news story on New Year's Day, the Butterfly House is happy to announce the first new arrival of 2016.  This zebra swallowtail emerged from its chrysalis last week.  Here it is being studied by Laney Barnhart.

Several volunteers bring home butterfly caterpillars during the summer, feeding them until they pupate, to provide a new brood when the Butterfly House opens in the spring. The plan is to bring the pupae out of storage in the spring in time for a new "graduating class" on opening day. The winter sleep is called “diapause’ and if the chrysalides are kept cool, and if the days are short, hatching will wait until spring.

However in this case, a caterpillar escaped and climbed to the underside of a cabinet to pupate.  It was not the first to have escaped and the first notice of this as the days lengthen is a butterfly fluttering around the house, wondering where all the flowers are.

The remarkable part of this story is.....January?  What was it possibly thinking?   Actually we don't know exactly what tells a butterfly when to eclose (emerge from its chrysalis).  In the wild, it is critical for the emergence to be timed to the presence of nectar sources and caterpillar food plants, in this case pawpaw leaves.  Clues could be the length of days, increasing mean temperature, or even some biological clock ticking away within the pupa.

The rest of its classmates formed their pupae and were stored out in the garage, where they see mainly normal light cycle and temperature. They are kept in a wine cooler, but it has a glass front, and it only chills them if there is a warm spell. The idea is to keep them on a normal schedule to emerge in the spring so  they are not in the dark, literally or figuratively. 

This zebra likely had no concept of the seasonal change by length of days. The house temperature was relatively stable and no sun reached its chrysalis under the cabinet.  Did it "think" it was March, the earliest time of normal emergence?  Either way this zebra swallowtail must have been very disappointed.

I recall a college roommate setting my alarm clock to wake me an hour early for an early morning class.  The position of the sun and the paucity of cars on campus didn't register until I found the building locked.  I can relate to this zebra's confusion.  The only "pawpaw" they could see was Chris.  That must have felt like the pull on the locked classroom door.

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