| Humpback whale | Competitive polygynandry | Multiple (per female/season) | Ephemeral (hours to days) | Long breeding songs, spectacular fights between males (“heat runs” of 5-20 males around one female). |
| Sperm whale | Visiting polygyny | Several males/season | Episodic visits by males | Solitary males move between matrilineal groups of females in the tropics. No territories. |
| Killer whale (resident) | Strict inter-pod exogamy | Outside the pod only | Brief encounter, no pair bond | Breeding takes place at multi-pod gatherings (“superpods”). Very strict incest taboo (matrilineal lineage). |
| Common bottlenose dolphin (Shark Bay) | Multi-level male alliances | Coalitions of 2-3 males | Alliances of 25+ years | Pairs/trios of males team up to escort (sometimes harass) females. Alliances of alliances (“super-alliances”). Documented by Connor. |
| Blue whale | Song polygyny | Multiple | Very brief | Males sing at very low frequency to attract females over very long distances (1000+ km). No direct competition. |
| North Atlantic right whale | Multiple breeding | Multiple males/female | Very brief | Courtship groups of several males around one female. Males have the HEAVIEST TESTES in the animal kingdom (~500 kg), extreme sperm competition. |
| Beluga | Seasonal promiscuity | Multiple | Brief | Breeding at summer gatherings in estuaries. Complex vocal communication. |
| Narwhal | Duelling polygyny | Multiple | Brief | Tusk fights (giant teeth) between males. Females choose the winners. The tusk is thought to be under sexual selection. |
| Harbour porpoise | Promiscuity | Multiple (extreme) | Very brief (~3 seconds) | Extremely rapid mating. The male has proportionally the LARGEST TESTES of any cetacean (10% of body weight). Extreme sperm competition. |
| Long-finned pilot whale | Breeding within the pod | No obligatory exogamy | Life in a stable pod | Like the killer whale, life in matrilines. But breeding is not strictly exogamous. |
| Pygmy sperm whale | Very poorly known | Unknown | Unknown | A discreet species, poorly documented in the wild. |
| Common dolphin | Promiscuity | Multiple | Brief | Breeding in large groups. Complex coordination for hunting + breeding. |
| False killer whale | Multi-male/multi-female society | Multiple | Stable pod | Life in stable pods including males and females. Breeding within the pod is possible. |
| Cuvier's beaked whale | Very poorly known | Unknown | Unknown | Linear scars on males = fights between males using their apical teeth. Intense competition. |
| Common minke whale | Promiscuity | Multiple | Very brief | Courtship vocalisations documented. Small breeding gatherings. |
| Grey whale | Competitive polygynandry | Multiple males/female | Brief | Breeding in the Mexican lagoons (Baja California). Breeding trios (2 males + 1 female) sometimes observed. |
| Bowhead whale | Promiscuity | Multiple | Very brief | The most varied breeding songs in the animal kingdom. Sperm competition (testes ~500 kg, as in the right whale). |
| Ganges river dolphin | Very poorly known | Unknown | Unknown | Solitary species or in small groups. Breeding rarely observed. |
