Alex Mustard / Yellowbelly hamlets (Hypoplectrus aberrans) pair spawning at dusk (artifically backlit). Hamlets are hermaphroditic species. George Town, Grand Cayman, Cayman Islands. Caribbean Sea.

Alex Mustard / Black hamlet (Hypoplectrus nigricans) and Yellowbelly hamlet (Hypoplectrus aberrans) spawning at dusk. As this genus is quite recently evolved hybridization is still possible. Hamlets are one of the...

David Noton / The village of Eus perched on a hilltop with sunlight with the Pic de Canigou beyond, the Pyrenees, Languedoc-Rousillon, France. June 2006.

Alex Mustard / Butter hamlet (Hypoplectrus unicolor) pair spawning at dusk, George Town, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

David Pattyn / Alpine ibex (Capra ibex) adult males in the hamlet of Pont in front of houses, Valsavarenche, Gran Paradiso National Park, Aosta Valley, Italy, may

Linda Pitkin / Spotted moray (Gymnothorax moringa) Bonaire, Leeward Antilles, Caribbean.

Linda Pitkin / Spotted moray (Gymnothorax moringa) Bonaire, Leeward Antilles, Caribbean.

Alex Mustard / Pair of Yellowbelly hamlets (Hypoplectrus aberrans) spawning at dusk. Hamlets are one of the few vertebrate species that are true hermaphrodites, here the fish with the open mouth is acting as a male...

Alex Mustard / Pair of Barred hamlets (Hypoplectrus puella) spawning at dusk . Hamlets are one of the few vertebrate species that are true hermaphrodites, here the fish in the foreground is acting as a male, but thi...

Andrew Cooper / Aerial view tracking over Whiteworks hamlet, showing evidence of past mining, Dartmoor National Park, Devon, England, UK, October 2015.

Claudio Contreras / Spotted moray (Gymnothorax moringa) on seabed, Playa del Carmen, Caribbean Sea, Mexico, January

Alex Mustard / Pair of Barred hamlets (Hypoplectrus puella) spawning at dusk. This species is hermaphrodite. Wreck of the Oro Verde, Grand Cayman, Cayman Islands. Caribbean Sea.