Jetsam ambergris, the waxy rocks of whale digestive material that wash up on beaches and are coveted by the perfume industry for their musky fragrance, have been convincingly tied to sperm whales through DNA analysis, according to a study published today (February 5) in Biology Letters.
Scientists have long suspected that the pungent blobs—which can weigh as much as 1,400 pounds—shared an origin with ambergris extracted directly from sperm whale colons, but there were no confirmations. The idea was backed up mainly by observations of the whale’s prey, such as undigested squid beaks, that accumulated in the digestive solids.
As whale populations declined between 1800 and the 1980s due to commercial whaling, it had become increasingly difficult to compare the two types of ambergris, which have different chemical compositions, reports The New York Times.
Researchers led by Ruairidh Macleod at the University of Cambridge extracted DNA from jetsam ambergris found on beaches in Sri Lanka and New Zealand and compared it to DNA from a beached sperm whale in the Netherlands. The DNA was in remarkably good condition because ambrein, the principle component of ambergris, is hydrophobic and resistant to the acidic environment of the colon, according to the study.
The team writes in its report that the “phylogenetic analyses unequivocally supported the sperm whale origin of the four ambergris samples.” Although the four samples used in the study were definitively attributed to sperm whales, the authors note that other deep-diving marine mammals may also produce ambergris.
“The discovery that ambergris yields such good DNA preservation opens up new opportunities for studying both the use of this precious raw material and whale biology,” University of Cambridge archeologist James Barret who did not participate in the study tells the Times.
The results may also improve scientists’ understanding of sperm whale ecology and evolution. Alana Alexander, a cetacean DNA researcher at the University of Otago in New Zealand, tells the Times that pre–whaling era DNA samples extracted from ambergris would help shed light on the history of the species.
Amy Schleunes is an intern at The Scientist. Email her at firstname.lastname@example.org.