During breeding season, male eastern fence lizards begin a push-up regimen. Flexing their forelimbs, they pump their sunbathed bodies in a rhythm herpetologists call “jiggling.” They flash bright blue side patches like Sons of Anarchy motorcycle jackets. Pigmented cell layers in their dermis and epidermis mirror blue and green wavelengths whose underlying crystalline structure Kinsley refers to as “the crystal lattice.”

An undergraduate biologist, Kinsley, has applied for a research grant, and I am a professor on the granting committee. Female lizards also have patches, she explains, though white or lighter blue and more often at the throat. As the sexes evolved, some females developed more coloration, but biologists don’t fully understand this morphing sexual dimorphism, or sexual differentiation, she wants to study.

I’m in. Any other semester real-time scrutiny of evolution by confocal microscope would earn my vote, but now it reflects the gender spectrum illumining our classrooms.

~

Leah requested on the first day that we call her Luke, an assertion of masculinity delivered with soft-spoken voice. I looked up from my roster, noting this name preference, searching for distinguishing facial characteristics, hair, clothing, before smiling into the eyes and moving on. I might have gone the whole semester letting this student shuttle in my mind not yet beyond gender, as the prefix trans- suggests, but between or inter-gender. Except. A sentence arose requiring a pronoun. I knew it was the wrong one the moment I spoke, scrambling to revise my antecedent to mean the author we were reading rather than Luke’s comment about her work.

When class was over, I strode to the office of our university’s director of Women’s Studies for guidance. “Ask the student,” she advised.

“I didn’t know we could be that direct,” I said, both relieved and intimidated by the conversation to come.

“As long as you phrase the question with respect,” she said, “she/he will appreciate that you want to know.”

~

The name of the genus Sceloporus originates from scent glands located at the fence swift’s thighs, the species undulatas from the ripple illusion created by its crossbars. Its name implies why gender is so compelling to study, since undulate, “to cause to move in a sinuous or flowing manner,” sprang from bars—places bois might shiver past or clock some former lover, dual as light that moves as both a particle and a wave.

~

Lizards show their strength in order to reduce threatening encounters by ruffling their lapis lats. Prompted by circumstances to show my colors, I can only imagine how Luke feels.

“There are brilliant reasons for making gender an active decision,” I begin my logistical heart-to-heart. “Since the name you’ve given us to call you is traditionally male while the one on my register is traditionally female, what are your preferred pronouns?”

“He/him,” he answers. Later, a SAFE Zone counselor says I can assume pronouns match the chosen name’s gender, though to do so propagates the binary some seek to dispel. Not Luke. He contributes more afterward to class discussions, lowers his hoodie away from his face, perches higher in his desk.

~

Kinsley states her theory so clearly, an interdisciplinary group of mathematicians, physicists, artists, and geographers agree to fund her project. She wants to prove that the number of irridophores beneath any individual’s skin is not the primary basis for its shading. Instead, compounds on the surface filter a prism of rungs from which only the brightest blues escape.

I look up “crystal lattice,” knowing it refers to more than my family’s wooden-slatted patio, and it does mean specifically “a set of infinite, arranged points related to each other by transitional symmetry.” Still, I picture the crosshatched diamonds I peered through as a child, scraping laceworks of frost with my thumbnail. That thin skin peeled, melted beneath my fingertips so cold it felt like hot candle wax. I touched the pads together again and again, sensing the riffle between apparent opposites.

~

In the wild, jiggling begins mid-April. Males competing for territory gorge their throats and flare dewlaps like chins jutting for a fight. They eyeball each other, circle, and if pushed, push back, tails whipping like snapped towels. In a few years Luke will lash out if his defense isn’t honored, to prove himself a man among men.

* Students’ names have been changed to respect their privacy.