Toothless whales as the names suggests don’t have teeth. Instead they use baleen, flexible plates that hang from the top jaw like curtains to filter food from the water. This feeding structure evolved millions of years ago when the oceans were full of toothy whales all competing for limited food.
It was a game changer, enabling some of the largest animals that have ever lived to consume some of the smallest and most abundant life in the ocean. The actual timeframe for this evolution has created enormous debate in the scientific community, with estimates ranging between 3-30million years ago. But it seems that answer has been hiding in the mouths of these giants all along… in their baleen.
Baleen is made up of keratin (the same materials as our nails and hair) and scientists have discovered that it’s layered like rings of a tree and holds chemical timestamps. Think of it as a chemical journal of the whale’s life. This discovery is revealing applications to answering evolutionary questions of the past as well as predicting the whale’s future, which is jaw dropping.
By studying whale baleen that has been stored in museums and baleen used different products ranging from boxes and jewellery dating back to the 1500s, this may hold some key insights into the evolutionary pathway of the great giants of the ocean, how they went from being from toothed to tooth-combed feeders.
There are also chemical clues imprinted in the baleen, which is providing scientists with a bounty of information, especially when it comes to hormones. Surprisingly, baleen plates grow continually throughout an animal’s life, and the hormonal information is continually captured and stored in the baleen.
What is really cool about this is that researchers can get information on the reproductive success, health, movements and maturity rates from different sections of the baleen for different time periods. When this is overlaid with environmental data such as sea temperatures, it will provide scientists with a valuable insight about the biology of baleen whales, which are notoriously difficult to study.
Like the gift that keeps giving and a storyteller with infinite stories, baleen can also tell us what the whale has been eating and where. Why is this important? It can provide an indication of ocean health and ocean productivity i.e. amount of phytoplankton, which is the basis of the marine food chain. It’s also a sign of overall ocean health.
In a rapidly changing environment it’s vital that we understand how these beautiful behemoths are dealing with changing oceans and ocean chemistry. Knowledge is power and this research will help build timelines and reveal scientific data that can protect whale populations into the future by assisting with policy development, conservation and management.
Don’t know your thoughts but where whaley whaley excited about where this is heading…
(Note: The author makes no apologies for her bad sense of humour and excessive use of puns)
More detailed information can be found here: http://www.smithsonianmag.com/science-nature/history-toothless-whales-180964717/