Maximum Number of Simultaneous Offspring — Odontoceti

In the vast majority of Odontoceti, the rule is clear: one calf at a time. Intensive parental investment — with long gestations and extended nursing periods — makes twins rare and demanding. The only exceptions in this group are the dwarf sperm whale and the sperm whale, which can occasionally produce up to two simultaneous offspring. This conservative reproductive strategy is typical of long-lived mammals.

Chart Data Table

References (with hyperlinked sources)

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