EPOW - Ecology Picture of the Week

Lizards of the Lava

Galapagos Lava Lizard (Microlophus albemarlensis), Family Tropiduridae
Fernandina Island, Galapagos, Ecuador

Explanation:  Perched on rough bit of lava, here in the Galapagos Islands of Ecuador, is the aptly-named Galapagos lava lizard.  The individual in the main photo, above, is clearly a male, what with its dorsal spinal crest and its black and reddish throat.  

Which species of lava lizard is this?
If you know what island you're on, there's only one answer,
because each island has but one species.
Here, we are on Santa Cruz Island, so this indeed
is the Galapagos lava lizard, Microlophus albemarlensis.

Here, on Fernandina Island, a Galapagos lava lizard is utterly dwarfed by
a Galapagos fur seal.  The lizard is being a bit stealthy here,
looking for an opportunity to alight upon the seal
and snatch a few insect snacks that typically accompany the seal.

And, still on Fernandina Island here, a short ways away
is this lava lizard looking for a perch on a resting marine iguana. 
Lava lizards are part of a diverse guild of "cleaner species"
that specialize on consuming ectoparasites and other
small organisms from the bodies of other, larger species. 

Lava lizards vary considerably in appearance and size
across the islands of the Galapagos,
such as with this individual also on Santa Cruz Island.
This is the result of truly remarkable adaptive radiation across the archipelago.

Such is life in the lava!