(Notes about the Galapagos Cactus come from Silversea Excursion publications): Arid conditions prevail in the Galapagos archipelago. Due to the geography, there are many drought resistant plants that can live with very little water. Much of the landscape is harsh and dominated by this type of vegetation.
The most common plant in the dry inland portions of the Galapagos is the cactus. These succulent plants are able to store water in their stems and leaves, allowing them to thrive in hostile climates and during times of drought.
Most cacti have spines, which have evolved from leaves. Spines serve several purposes. They guard against predation, provide shade to keep the internal temperature of the plant lower, and the spines channel rainwater towards the base of the plant.
Another important adaption of the cactus is the waxy coating that covers the skin. This is called the “glaucus bloom” and it reduces evaporation as the plant seals in moisture. Leaf-like stems, known as "pads" store and conserve moisture and work as photosynthetic organs for the cacti.
Endemic cacti in the Galapagos Islands include the Lava Cactus, Candelabra Cactus, and the species of Prickly Pear.
We watched a Land Iguana climb a Prickly Pear and strip a portion of its spines so that it could take a bite! Check it out here: