IN FOCUS: SALAMANDERS

Salamanders range in size from Mexico’s minute salamanders – 2.7cm nose to tail – to the Chinese giant salamander, which reaches 1.8m and weighs up to 65 kg.

Salamanders can regenerate lost tails, limbs, toes and even severed spinal cords within weeks. Research has shown their cells retain “memory” much like mammal stem cells, offering a pathway for human medical science.

Salamanders are skilled at self-defence: some (such as Ambystoma maculatum, below) have glands on the neck or tail that secrete a powerful poison; others have garish skin to warn away predators. One species can push out its ribs until they pierce through its skin and combine with secretions to act like poisonous barbs.

Salamanders don’t have ears; they feel vibrations in the ground with their body. Experiments suggest some species can “hear” sound waves via vibrations in their lungs, providing hints into how land animals evolved fully functional ears.

Salamander brandy – purported to have hallucinogenic and aphrodisiac effects – was popularised in the 1990s. The active ingredient was likely samandarin, a toxic compound secreted on the skin of the fire salamander.

The spotted salamander A. maculatum grows to 15-25cm long and is commonly found in North America’s east. The species follows the same annual migration path, mating and laying eggs in ephemeral, fish-free pools of water. A. maculatum has a mutualistic relationship with the algae Oophila amblystomatis, which protectively encases the eggs and lives inside embryos and larvae in the only known example of “endosymbiosis” in a vertebrate species.