Heat seekers

These sacred ibis are well insulated, with only their eyes and one leg losing heat Photograph: Steve Lowe/Zoological Society of London

By changing the parameters on the thermal camera, the veins running through this butterfly’s wings are clearly visible Photograph: Steve Lowe/Zoological Society of London

These flamingos have brilliant insulation, allowing heat to escape only through one leg Photograph: Steve Lowe/Zoological Society of London

The coarse hair on this warthog’s back helps keep him cooler Photograph: Steve Lowe/Zoological Society of London

Lucifer the lion’s mane isn’t allowing any heat to escape Photograph: Steve Lowe/Zoological Society of London

Three silvery marmosets dangle their cool tails behind them Photograph: Steve Lowe/Zoological Society of London

Fatty the meerkat enjoys a turn under his heatlamp Photograph: Steve Lowe/Zoological Society of London

Asian short-clawed otters Photograph: Steve Lowe/Zoological Society of London

This pelican, which had just stood up after sitting on its feet, has left a clear trail of warmer footprints behind it Photograph: Steve Lowe/Zoological Society of London

Three South African black-footed penguins trundle along the edge of their cold pool Photograph: Steve Lowe/Zoological Society of London

The cold nose of this sloth is clearly visible as it clambers through Rainforest Lookout Photograph: Steve Lowe/Zoological Society of London

A closer look at the Mexican red-kneed bird-eating spider shows that the tips of its legs are the coolest areas Photograph: Steve Lowe/Zoological Society of London

The dark stripes on these zebra clearly show up as warmer than the white areas because they absorb heat instead of reflecting it Photograph: Steve Lowe/Zoological Society of London