University of Memphis Researchers Uncover Ancient Origins of Insect Smell
NSF-funded study reveals how insects evolved the genetic toolkit behind one of nature’s most important sensory systems
A new study led by University of Memphis researchers has uncovered important clues
about how insects evolved their remarkable ability to smell and taste—an evolutionary
breakthrough that helped make insects one of the most successful groups of organisms
on Earth.
Published in Nature Communications, the research traces the deep evolutionary origins of the genes insects use to detect chemical signals in their environment, offering new insights into how these sensory systems emerged and diversified over hundreds of millions of years.
Publication: Nature Communications
Title: Early hexapod genomes reveal the deep origin of insect gustatory and odorant receptors
The study was conducted by Dr. Duane McKenna, William Hill Professor of Biology and Director of the Center for Biodiversity Research at the University of Memphis, Dr. Kevin Moran, a postdoctoral researcher in the McKenna Lab, and Dr. Robert Mitchell of The Pennsylvania State University. The work was supported by the National Science Foundation through a grant awarded to McKenna and Mitchell.
Insects depend on smell and taste to navigate nearly every aspect of their lives—from finding food and mates to avoiding predators and locating suitable habitats. To understand how these abilities evolved, the research team analyzed genomes from insects and their closest relatives, reconstructing the evolutionary history of the genes responsible for detecting chemical cues.
Their findings revealed a previously overlooked group of taste-receptor genes and identified genetic precursors to the odorant receptors insects use to smell. The results suggest that the sophisticated smell receptors found in modern insects likely evolved from older taste-related sensory systems.
“Insects live in a world of chemical information,” said McKenna. “This study helps explain how insects evolved the genetic toolkit that lets them sense and respond to that world.”
To uncover these evolutionary connections, the researchers expanded their analysis beyond well-studied insects such as flies, moths, and beetles. By examining early branches of the insect family tree and non-insect hexapods—small, wingless relatives of insects—the team identified genetic evidence that had been overlooked in previous studies.
“One of the most exciting parts of this work is that some key clues were hidden in plain sight,” said Moran. “By looking carefully across many genomes, we found receptor lineages that help connect insect taste and smell.”
According to Mitchell, the findings shed light on one of the defining innovations in insect evolution.
“Odorant receptors are one of the defining innovations of insects,” Mitchell said. “Our results show how that innovation likely emerged from older chemosensory systems and became central to insect diversity and success.”
The discovery advances scientific understanding of sensory evolution while demonstrating the power of comparative genomics to answer fundamental questions about biodiversity and adaptation. The work also highlights the University of Memphis’ growing leadership in evolutionary biology, genomics, and biodiversity research.
For more information, contact McKenna at dmckenna@memphis.edu, or Mitchell at rfmitchelle@psu.edu.