DNA study reveals Australia’s six-legged ‘land lobster’ still exists

Australia’s stick insect (Dryococelus australis) that was once thought to be extinct actually still exists, according to scientists who compared the DNA of a museum specimen with the DNA of a similar-looking insect discovered on Ball’s Pyramid, a volcanic outcrop located about 14 miles away from the Lord Howe Island.

The insect was wiped out from the island by 1930s

Lord Howe is a small island located about 400 miles east of Australia in the Tasman Sea. In 1918, wreckage of the British supply ship Makambo near the island allowed black rats to enter this isolated territory.

The rats soon started feasting on island’s native bug—a big, flightless insect that appeared like a stick and was also called "Land Lobster". The result of this prolonged feast was that the bug was completely wiped out from the island by 1930s. During later years, it was believed that Dryococelus australis had probably gone extinct.

In 1964, a group of hikers while exploring the area of Ball's Pyramid volcano found a dead insect that appeared similar to the land lobster. In 2001, researchers again found several black bugs in the same region. These insects were somewhat thinner and had a different tail end compared to stick insect. The discovery puzzled researchers who were unaware whether the newly found bugs were an evolution of the fabled land lobster or something else.

DNA analysis of the two bugs

To solve the puzzle, a team of researchers recently carried out DNA analysis of the two bugs to find that their DNA differed from each other by less than 1%. They have some morphological differences but are definitely the same species. The finding suggests that the two populations probably diverged from each other — not a long time ago in biographical evolutionary terms — after the origin of the species.

According to researchers, the newly-found insect features a segmented body and can grow to big sizes, up to 6 inches in length. It prefers to remain hidden on trees during daytime and comes out only at night to eat green shrubbery. The babies of this insect are bright-green in color and can be seen during the daytime.

Rodent eradication program

Less than 30 adult land lobsters are now left on Ball’s Pyramid. Researchers are trying to get this rare insect back to its native place—the Lord Howe Island. In the past few years, the captive breeding programs by Melbourne Zoo have helped their population flourish to some extent. The Lord Howe Island authorities are also planning to launch a rodent eradication program next year to let the land lobster recover from near eradication.