Whale Facts and Characteristics

Overview of Whales (Cetaceans)

Whales belong to the animal order called cetaceans.
Cetaceans are divided into two subgroups:
- Toothed whales
- Baleen whales
Despite living in water, they are mammals:
- Give birth to live young
- Nurse with milk
- Are warm-blooded
- Have hair, called lanugo before birth

Whales descended from land animals:
- Ancestors crawled out of water 375 million years ago, back to water 50 million years ago.
- Early cetaceans hunted in water, evolved aquatic features.
Anatomical adaptations:
- Nostrils migrated to the top of the head (blowholes).
- Baleen whales have two blowholes, toothed whales have one.
- Male whales have backbones anchoring their penises.
Ear anatomy:
- Whales have ears but no external ear structures.
- Earwax accumulates and can be used for research.

Toothed whales:
- Use echolocation for hunting and navigation.
- Produce clicks in nasal passages, focused by "melon" tissue, received by lower jaw.
Baleen whales:
- Do not use echolocation.
- Humpback whales are known for complex songs.

Whales are carnivorous and eat various marine animals:
- Toothed whales (e.g., orcas, dolphins) eat fish, squid, seals.
- Baleen whales filter feed on krill, plankton, small fish.
Rorqual whales have specialized feeding techniques:
- Take large gulps, use baleen plates to filter food.
Narwhals:
- Males have elongated tusks (canine teeth).
- Tusks possibly serve sensory or mating purposes.

Whales' ecological roles:
- Blue whales can consume up to four tons of food daily.
- Whale poop acts as fertilizer, aiding nutrient cycling in ocean ecosystems.
Record-holding species:
- Cuvier’s beaked whale dives up to 3,000 meters.
- Bowhead whales can live up to 200 years (evidence from embedded harpoons).