Why in the news?

A recent study has uncovered the intricate structure of their communication system, which appears to possess a “phonetic alphabet,” offering new insights into the depth of their social interactions.
- Sperm whales, the largest toothed whales, utilize a diverse array of vocalizations to communicate, including bursts of clicking noises known as ‘codas’.

About Sperm Whales (Physeter macrocephalus)).

Sperm whales, the largest toothed whales
It has a series of vertical creases or wrinkles on its body and a small, inconspicuous dorsal fin located near the rear of its back.
The sperm whale uses ‘echolocation’ to navigate and locate prey during these deep dives.
- Prey: Sperm whales primarily feed on squid (including the giant squid) sharks and deep-sea fish.
- Habitat: Sperm whales are found in deep oceanic waters worldwide, from the equator to the edges of the pack ice in the Arctic and Antarctic.
- Behavior: Known for their exceptional diving capabilities, sperm whales can dive to depths of over 2,000 meters (6,560 feet) and stay submerged for up to 90 minutes. They are social animals, typically found in groups called ‘pods’, which can contain up to twenty individuals.
Conservation Status: Listed as ‘VULNERABLE’ by the IUCN.
- Threats cause: Collisions with ships, entanglement in fishing gear, and noise pollution.

Expressivity: The study, which utilized data from Project CETI demonstrated that sperm whale calls exhibit a broader range of expressivity than previously recognized, hinting at a nuanced mode of communication.
Social Dynamics: Like all marine mammals, sperm whales rely heavily on vocalizations as an integral aspect of their social interactions.
Contextual Analysis: The next phase of research aims to decipher the behavioural context surrounding sperm whale vocalizations, shedding light on their potential meanings.

Project CETI is a non-profit, interdisciplinary scientific and conservation initiative on a mission to listen to and translate the communication of sperm whales off the island of Dominica in the Eastern Caribbean.

[2013] Consider the following animals

Which of the above is/are mammal/mammals?

(a) 1 only

(b) 1 and 3 only

(d) 1, 2 and 3