The Buffalofish: A Century-Old Aquatic Species with Astonishing Aging Potential

Thursday - November 2 2023, 22:54 UTC - 1 year ago

Scientists have identified the second-known genus of animals that boasts three or more species with lifespans exceeding a century. This remarkable find has the potential to expand research in various fields, including those focused on gerontology and vertebrate senescence, offering new insights into longevity. A recent study from the University of Minnesota Duluth focused on the buffalofish genus within Ictiobus, including three species native to Minnesota - bigmouth buffalo, smallmouth buffalo, and black buffalo. Instead of examining the fish’s scale, scientists determined age by extracting otoliths from the cranium and forming a new layer each year. Results of the study show buffalofishes are native to central North America, but those in this recent study were found in Apache Lake, a reservoir in the desert southwest. This research raises the question of what their “fountain of youth” is.

A recent study found some of the oldest animals in the world living in a place you wouldn’t expect: fishes in the Arizona desert. Scientists have identified the second-known genus of animals that boasts three or more species with lifespans exceeding a century. This remarkable find has the potential to expand research in various fields, including those focused on gerontology and vertebrate senescence, offering new insights into longevity.

The study centers around a series of fish species within the Ictiobus genus, known as buffalofishes. Minnesota has native populations of each of the three species studied: bigmouth buffalo, smallmouth buffalo and black buffalo. The importance of this research is underscored by the fact that these fishes are often misidentified and lumped in with invasive species, like carp, and the fishing regulations in many places, including Minnesota, do not properly protect these species, and what could become a wealth of information about longevity and aging.

This new research from the University of Minnesota Duluth (UMD), recently published in Scientific Reports, was a collaboration between Alec Lackmann, PhD, an ichthyologist and assistant professor in the Department of Mathematics and Statistics of the Swenson College of Science and Engineering at UMD; other scientists including from North Dakota State University; and a group of conservation anglers who fish the Apache Lake reservoir in Arizona.

"There is likely a treasure trove of aging, longevity, and negligible senescence information within the genus Ictiobus," said Lackmann. "This study brings light to this potential and opens the door to a future in which a more complete understanding of the process of vertebrate aging can be realized, including for humans. The research begs the question: what is the buffalofishes fountain of youth?" University of Minnesota .

Lackmann has studied buffalofishes before, and his research from 2019 went so far as to extend the previously thought maximum age of bigmouth buffalo from around 25 years of age, to more than 100 years of age by applying and validating a far more refined aging technique than had been used previously. Instead of examining the fish’s scale, "you extract what are called the otoliths, or earstones, from inside the cranium of the fish, and then thin section the stones to determine their age," said Lackmann.

Approximately 97 percent of fish species have otoliths. They’re tiny stone-like structures that grow throughout the fish’s lifetime, forming a new layer each year. When processed properly, scientists like Lackmann can examine the otolith with a compound microscope and count the layers, like the rings on a tree, and learn the age of the fish.

Results of the study include: .

Buffalofishes are native to central North America, including Minnesota, but those in this recent study were found in Apache Lake, a reservoir in the desert southwest. Originally reared in hatcheries and rearing ponds along the Mississippi River in the Midwest, the government stocked buffalofishes into Roosevelt Lake (upstream of Apache Lake), Arizona in 1918. While Roosevelt Lake was fished commercially over the years, Apache Lake has never been stocked with buffalofishes other than the original 1918 stockings.