Detecting giant clams in the Red Sea

A new giant clam has just been found in the Red Sea, with deep folds on the shell.

Son with deep zigzag grooves on the shell.Photo: BBC.

The fossil data suggest that about 125,000 years ago, this Tridacna costata accounted for more than 80% of the region's giant male population. But now, they may have become extremely dangerous.

Scientists believe their findings may testify to one of the earliest examples of human excessive marine exploitation.

Tridacna costata has very strange characteristics that make it different from the other two giant clams in the Red Sea. Those are zig zag looks on the body of the shell. They are 40 cm long and weigh about 2 kg. A distant relative of them can reach 1.4 meters long.

The living boys seem to only be restricted to very shallow waters, while other species are distributed in deeper coral zones. In addition to living specimens, intact fossil samples were also unearthed, indicating that their population had declined dramatically by about 125,000 years ago. But the cause is said to be hunted by humans for meat.