Meet the Suspects

A red deep-sea fish specimen.
This deep sea creature has a whale-like body and gaping mouth. It grows up to 400 mm (15.7 in) long. (Kunio Amaoka)

More than a century ago, in 1895, two Smithsonian scientists described a new kind of deep sea creature living at least 1000 m (3,280 ft) below the ocean’s surface—a part of the ocean that we still know very little about.

The scientists named their find the whalefish because of its whale-like appearance. Little did they know that this fish would become one of the prime suspects in a mystery that took scientists from around the world decades to solve.

Tapetail fish with long tail.
This fish’s tail looks like a long streamer. It grows only up to 45 mm (1.7 in) long. (Chris Kenaley)

The Mystery Develops

Flash forward to 1956, when scientists described another new kind of fish. It was named the tapetail because of its long, streamer-like tail. It also had a large upturned mouth.

Unlike the whalefish, the tapetail was found living near the ocean’s surface. And there was something very curious about this sea creature: Every single one of the 120 tapetail specimens scientists studied was a larva or juvenile.

Where were all the adults?

The Plot Thickens

In 1966, based on 11 specimens, scientists added another deep sea creature to the list of mystery suspects: the bignose fish, found living deep in the sea like the whalefish. It has an unusual nose-like bulge on its snout with large organs for smelling. Its upper jaw can’t move. And something else proved odd about the bignose fish: Of the 65 specimens now collected, everyone is a male. Where were the females?

Then, in 1989, the whalefish also became a suspect. An Australian scientist studied all the whalefish specimens collected so far—a total of over 500 from all over the world. Every adult was a female. Where were the males?

October 2010