Marine mammals, birds, and reptiles expend a significant amount of energy in their movements. For instance, humpback whales (Megaptera novaeangliae)
Turtles and penguins have a swimming sweet spot that reduces drag

Marine mammals, birds, and reptiles expend a significant amount of energy in their movements. For instance, humpback whales (Megaptera novaeangliae)
As the day comes to a close in the UK, and the final moments slip away like sand through a