Trilobites: Baleen Whales Intermingled as They Evolved, and Share DNA With Distant Cousins
Baleen Whales Intermingled as They Evolved, and Share DNA With Distant Cousins Photo Fin whales differ in size, color and body shape from their cousins, the larger blue whale, but scientists decoding the genome of several baleen species say there was intermingling during the course of their evolution. Credit Florian Schulz For years, scientists have disagreed about which species of baleen whale came first, and how the toothless species were related.
Body structure suggested one set of relationships; molecular data suggested another.
Now, researchers in Germany and Sweden have sequenced the DNA of six of the living species, of which there are at least 10.
The relationships are so complicated, however, that senior researcher Axel Janke said that “family tree” is too simple a metaphor. Instead, the species, all part of a group called rorquals, have evolved more into a network, sharing large segments of DNA with even distant cousins. Scientists expressed surprise that there had been so muc..