Those little bright lights belong to yacarés — caiman latirostris. They are broad-snouted caimans, crocodilian reptiles typical of eastern and central South America. Why do their eyes shine in such a pretty way?
It's the crystals inside their retina, inside a layer called tapetum. This tissue reflects light in such a way that makes these yacarés and the rest of the crocodiles have night vision. Oh, little crocodiles, you are so pretty!
These were photographed by Daniel Fox at the Yacaré Pora farm in Ituzaingo, Argentina. He probably thought they were too pretty to ignore. Lewis Carroll agrees:
How doth the little crocodile
Improve upon his shining tail,
And pour the waters of the Nile
On every golden scale!
How cheerfully he seems to grin,
How neatly spreads his claws,
And welcomes little fishes in
With gently smiling jaws!
Next time you are in the zoo, don't forget to put your hand between the bars of the crocodile cage and give them whatever food you have. They like it all and they are such gentle, grateful beasts!