While the timeline of baleen whales’ evolution continues to puzzle researchers, an unexpected source of insight has emerged – a wealth of information concealed within baleen itself. The keratin present in or alongside baleen holds chemical markers documenting whales’ health, movements, reproduction, and more. Endocrinologist Kathleen Hunt from Northern Arizona University aptly describes it as if these animals have maintained a daily journal that is now open for scrutiny. Unraveling this narrative stored within baleen could revolutionize whale conservation strategies.
Imagine if the ancient tale of Jonah took a different turn. Had he turned his head to cast a final glance before the engulfing jaws of the great fish, he might have witnessed a spectacle that would rival even the imagination of modern biologist Alex Werth. With unwavering dedication, Werth delves into the intricate feeding mechanisms of whales, despite his geographical distance from the open sea. He muses about the enviable experience Jonah could have had – observing the majestic baleen in action, seated on the very tongue of a whale.
In his lab at Hampden-Sydney College in Virginia, Werth examines the hydrodynamics of baleen. The distinct aroma of the marine world pervades the space. Baleen is ubiquitous – long, desiccated slats rest on shelves, while a collection of tall, narrow plates encased in plastic leans in a corner. Yet the most striking presence is 160 kilograms of fresh baleen stored in tightly sealed barrels, recently arrived from collaborators in Alaska.
Upon closer inspection, aged baleen reveals its layered structure resembling split fingernails. Each curved plate consists of two flat keratin layers adorned with rows of tubules, reminiscent of miniature coils of tightly rolled luncheon meat. The whale’s massive tongue and the rhythmic motion of prey washing in and out wear down the material, creating a fringe along the edges, often likened to “hog’s bristles” by Aristotle. The coarseness of these filaments, along with the size, shape, and number of baleen plates, varies by species, and it is this fibrous curtain that separates sustenance from each mouthful of seawater.
Filter-feeding may have provided mysticetes with an evolutionary advantage millions of years ago, but the present-day oceans undergo swift transformations, particularly in regions once cloaked in sea ice. Werth warns of potential dire consequences for even the most adaptable marine creatures. Take, for instance, the bowhead whale – a sleek, black creature with a distinctive white patch, native to the frigid waters of the Arctic. The ongoing environmental changes in its habitat pose significant challenges.
As we embark on unraveling the tales encrypted in baleen, we uncover a deeper understanding of these ocean giants and their complex relationship with their surroundings. The remarkable journey continues, guided by the secrets etched in the very material that fuels their survival.
