The recent discovery of a new beaked whale species, one that was believed to be a variant of a previously described species, is a reminder that our understanding of cetaceans is still limited. Humans have revered whales, and hunted whales, for centuries. They’ve been woven into folklore and turned into a variety of products. But, they are difficult to study. They spend most of their lives below the ocean’s surface and don’t speak human. Conversely, we can’t hold our breath for very long and we don’t speak whale. So, getting to know them well is a challenge.
Researchers have gotten creative and collaborative, developing satellite tags that attach via suction cup, using drones fitted with bridal veil to catch whale’s spray when they exhale, collecting and analyzing fecal matter and using DNA technology to confirm, or reclassify, the existence of a new species. That is the case with the as yet unnamed new species of beaked whale. It has been interesting to periodically check in on the web site of the Society for Marine Mammalogy to see what they list as the number of whale, dolphin and porpoise species (about to become 90 again), and to read the logic regarding their decisions.
Here’s a quick peek into some other recent discoveries:
The Cuvier’s beaked whale (Ziphius cavirostris) has the deepest dives (9816 feet (2992m) and 137.5 minutes) of any marine mammal. A team of researchers, led by Gregory Schorr of Cascadia Research Collectives, made this discovery in 2014 after sifting through 3,700 hours of data collected with satellite tags. (Gregory Schorr, PLOS One, March 2014).
Another species of beaked whale, now known as Deraniyagala’s beaked whale (Mesoplodon hotaula), was confirmed in 2014. This species was originally given this name in 1963, but was reclassified in 1965 as a gingko-toothed whale (Mesoplodon gingkodens). A review of DNA and physical characteristics, led by Dr. Merel Dalebout of Univ of New South Wales, Australia, led to the proper taxonomic recognition and placement of this species. (Merel Dalebout, Marine Mammal Science, February 2014).
Humpbacks whales, arguably the most recognizable type of whale, are a global species. We now know that their cultural habits and migration patterns have led to genetic diversity. A team led by Dr. Scott Baker from Oregon State examined 2200 biopsy samples of North Pacific humpbacks. Their research has determined that there are five distinct humpback whale populations in the North Pacific. This new information may prove critical when decisions are made regarding the level of protection these animals receive. (Scott Baker, Marine Ecology – Progress Series, 2013).
Whales are adaptable, intelligent animals. One impressive example of this ability to adjust behavior to maximize survival is exhibited by the Blainville’s beaked whale (Mesoplodon densirostris). In an effort to avoid predators like the orca, Blainville’s remain silent until they reach a depth of 560 ft (170m), at which point they will begin to communicate and echolocate to hunt. Orcas tend not to dive to these depths to find food. (Natacha Aguilar, Marine Mammal Science, July 2011)
Most of the recent discoveries of new cetacean species involve animals with teeth. The one exception is the Omura’s whale (Balaenoptera omurai), first classified in 2003. This whale was previously thought to be a variant of the Bryde’s whale (Balaenoptera edeni). It is definitely a distinct species. This National Geographic story provides some great photos and information about this whale. Featured in the article is Dr. Salvatore Cerchio who was a panelist here at the NBWM two weeks ago when we aired the film, Sonic Sea.
Along with this new knowledge of existing species, fossil species are being discovered on a regular basis. Two species of dolphin, Echovenator sandersi, (Morgan Churchill, Current Biology, 2016) and Isthminia panamensis (Nick Pyenson, PeerJ, September 2015) have been unearthed and described.
An important transitional species, from 27 million years ago, that had both baleen and teeth, Sitsqwayk cornishorum (Carlos Mauricio Peredo, Papers in Paleontology, July 2016) adds to our understanding of the evolution of baleen whales. Lastly, a re-examination of a fossil skeleton found 90 years ago, has led to the introduction of a new genus, Albicetus, (white whale), into the sperm whale family tree. This whale lived between 5.3 and 23 million years ago.