According to Oddity Central, scientists believe that Methuselah is a female fish, although they cannot confirm it. People who peek at her through the glass wall seem to not stress her out at all, and this fish still enjoys observing the visitors.

"He was initially given the unofficial title as the oldest fish in captivity in 2017, when experts estimated his age to be around 84 years old. However, newer tests have shown that Methuselah is even older than previously estimated, at least 92 to 101 years old."

This is difficult to ascertain, but some experts believe that old fish have several recognizable signs such as changes in the spine, weight loss, cloudy eyes, and even graying scales. However, none of these signs have been observed in Methuselah.

"We don't know if it's related to its age," said the aquarium director about Methuselah's color change over the years. "But that's the only thing we see physically that looks different on this fish," he continued.

Methuselah and his species still hold many secrets, but scientists are determined to uncover most of these secrets. For now, he is the oldest fish in captivity, and judging from his agile appearance, he may hold onto that title for some time.