Forty Acres Field Guide: Zebra Longwing Butterfly

By Dorothy Guerrero in 40 Acres Field Guide, July | August 2013 on June 25, 2013 at 11:55 am | No Comments

UT is an urban university in the heart of the city, yet the campus and its environs teem with fascinating plants and animals—from tropical parakeets to the world’s weirdest cactus.

Zebra Longwing Butterfly
(Heliconius charitonius)

High above the Forty Acres, on the roof of the Patterson Building on 24th and Speedway, there is a Central American rainforest. Larry Gilbert created this environment—and a similar habitat at the Brackenridge Field Laboratory—in the 1970s to study the relationship between butterflies and their preferred host plants, passion vines, where they lay their eggs. Theresa Freiburger, BS ’10, a full-time technician, is the caretaker of the flora and fauna that fill the large greenhouses here. By the time August rolls around, these glass structures become punishingly hot and humid, but it doesn’t seem to bother Freiburger. She cheerfully works away, grateful not to be behind a desk.

As she leads me on a tour through the greenhouses, she catches butterflies by gently pinching their wings, and then shows me the unique colors and patterns that mark each one. Freiburger mastered this technique as an undergrad studying ecology, evolution, and behavior, and today she can grab butterflies without brushing off a single scale. They hang between her fingers calmly, like kittens caught by the scruffs of their necks.

One especially striking species is the aptly named zebra longwing, whose black-and-white striped wings flutter wildly around us. These butterflies have an unusually aggressive mating ritual, known as pre-pupal mating. Male zebras attach themselves to a female’s cocoon, and hang there waiting for her to emerge. “They will not let go,” Freiburger says as she shows me two males glued to a brown pod hanging from a vine.

At the field lab, Gilbert guides me through the maze of tropical vines that grow in the lab’s gymnasium-sized greenhouse. It is sweltering. Through the orange trees and the flapping butterfly wings, he leads me to a fig tree as old as his storied career at UT. The odd sound of a croaking green tree frog fills the air while we stand and watch the busy insects around us. Gilbert says he can’t be in the rainforest all the time, so he brought it here to Austin. “They’re pretty happy in here,” he says, staring at a hovering zebra. “And I am, too.”

To read the rest of the Forty Acres Field Guide, click here.

Illustration by Jason Holley.

Tags: Brackenridge Field Laborartory, Larry Gilbert, Theresa Freiburger, zebra longwing butterfly