http://www.nytimes.com/ 
At the lab, an agreeably shabby workspace filled with vintage
boxy-looking gear and bugs stacked in jars and vials and glassine
envelopes and impaled on pins, Dr. May placed the slaty skimmer in a jar
with a piece of paper soaked with solvent; its flapping decelerated and
stopped. He snipped out the plate to which the penis was attached,
squeezed the seminal vesicle, hard-boiled the genitalia for five minutes
in a beaker of ethanol and admired them under the microscope. The lateral lobes” — oarish projections from the fourth and final
segment — “are nice and long and spread really widely,” he said. “And
the inflatable parts are large and have little hairs on them. You can
see it’s a complex organ.”
But just what the skimmer’s lateral lobes do is a mystery. Perhaps they function as specula to spread the vaginal canal to allow other penis parts access. Or maybe they reach into the female’s secondary sperm-storage side-sacs, the spermathecae, to remove sperm, though they seem poorly located and insufficiently grabby for the task. Or they might grab the rival’s sperm from the main sperm-storage area, the bursa copulatrix. An answer could come when Dr. May gets to dissecting the females, a process he is just beginning.
Likewise the puffy, bristly structure at the end of the penis known as the median lobe. “That may be some kind of currycomb that scrapes the sperm out of the bursa copulatrix. But again, we don’t know.” The smooth hood behind the median lobe, and the thumblike, stubbled anterior lobe? Functions unknown. Ditto the skinny, hornlike cornu.
Dr. May also hopes to determine whether differences in genital morphology can be used to help map the relationships between genera within families of odonates.
“I think I’ll end up with at least a partial answer to whether there are enough similarities between similar but not really closely related species to use as a taxonomical tool,” he said.
Young Michael May was enrolled in graduate school in biochemistry at the California Institute of Technology when he had second thoughts and took a job in Florida in 1969 as a lab assistant to his college roommate’s father, who happened to be an author of the original “Dragonflies of North America.”
“The moment the scales fell from my eyes, I was looking at a forktail through a hand lens,” he said — a male Rambur’s forktail damselfly, green-eyed, with a greenish-blue thorax and tail bookending a black-and-yellow-barred abdomen. Damselflies are the ones that can fold their transparent wings along the length of their dainty bodies, an ability dragonflies lack. “I thought, ‘Wow, I never realized they had all these different colors and parts.’ ”
Since then, he has stalked odonates on six continents and in most of the United States (his official portrait on the entomology department’s Web site shows him feeding a dollar into a bait-vending machine in upstate New York, beneath the caption “Dr. May collecting dragonfly larvae”). He has used molecular data to map family trees; demonstrated that dragonflies regulate their body temperature by “shivering” their flight muscles, an ability they share with some large moths, bees and beetles; and taken part in a study that tracked dragonfly migrations by gluing radio transmitters to their thoraxes.
His present project depends on obtaining fresh specimens because once a dragonfly has been preserved, its genitals cannot be inflated. But New Jersey has sufficient density of species of the most common and diverse dragonfly family, Libellulidae, to allow him to make meaningful progress, he says.
Dr. May acknowledges, though, that he has embarked on a bit of a fishing expedition with no clear endpoint or payoff. It is a risk that at this stage in his career he is willing and happy to take.
“I may end up with lots of pictures of weird penes,” he said, “and never really figure out satisfactorily how things fit together.”
At the lab, an agreeably shabby workspace filled with vintage
boxy-looking gear and bugs stacked in jars and vials and glassine
envelopes and impaled on pins, Dr. May placed the slaty skimmer in a jar
with a piece of paper soaked with solvent; its flapping decelerated and
stopped. He snipped out the plate to which the penis was attached,
squeezed the seminal vesicle, hard-boiled the genitalia for five minutes
in a beaker of ethanol and admired them under the microscope. The lateral lobes” — oarish projections from the fourth and final
segment — “are nice and long and spread really widely,” he said. “And
the inflatable parts are large and have little hairs on them. You can
see it’s a complex organ.” But just what the skimmer’s lateral lobes do is a mystery. Perhaps they function as specula to spread the vaginal canal to allow other penis parts access. Or maybe they reach into the female’s secondary sperm-storage side-sacs, the spermathecae, to remove sperm, though they seem poorly located and insufficiently grabby for the task. Or they might grab the rival’s sperm from the main sperm-storage area, the bursa copulatrix. An answer could come when Dr. May gets to dissecting the females, a process he is just beginning.
Likewise the puffy, bristly structure at the end of the penis known as the median lobe. “That may be some kind of currycomb that scrapes the sperm out of the bursa copulatrix. But again, we don’t know.” The smooth hood behind the median lobe, and the thumblike, stubbled anterior lobe? Functions unknown. Ditto the skinny, hornlike cornu.
Dr. May also hopes to determine whether differences in genital morphology can be used to help map the relationships between genera within families of odonates.
“I think I’ll end up with at least a partial answer to whether there are enough similarities between similar but not really closely related species to use as a taxonomical tool,” he said.
Young Michael May was enrolled in graduate school in biochemistry at the California Institute of Technology when he had second thoughts and took a job in Florida in 1969 as a lab assistant to his college roommate’s father, who happened to be an author of the original “Dragonflies of North America.”
“The moment the scales fell from my eyes, I was looking at a forktail through a hand lens,” he said — a male Rambur’s forktail damselfly, green-eyed, with a greenish-blue thorax and tail bookending a black-and-yellow-barred abdomen. Damselflies are the ones that can fold their transparent wings along the length of their dainty bodies, an ability dragonflies lack. “I thought, ‘Wow, I never realized they had all these different colors and parts.’ ”
Since then, he has stalked odonates on six continents and in most of the United States (his official portrait on the entomology department’s Web site shows him feeding a dollar into a bait-vending machine in upstate New York, beneath the caption “Dr. May collecting dragonfly larvae”). He has used molecular data to map family trees; demonstrated that dragonflies regulate their body temperature by “shivering” their flight muscles, an ability they share with some large moths, bees and beetles; and taken part in a study that tracked dragonfly migrations by gluing radio transmitters to their thoraxes.
His present project depends on obtaining fresh specimens because once a dragonfly has been preserved, its genitals cannot be inflated. But New Jersey has sufficient density of species of the most common and diverse dragonfly family, Libellulidae, to allow him to make meaningful progress, he says.
Dr. May acknowledges, though, that he has embarked on a bit of a fishing expedition with no clear endpoint or payoff. It is a risk that at this stage in his career he is willing and happy to take.
“I may end up with lots of pictures of weird penes,” he said, “and never really figure out satisfactorily how things fit together.”
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