The Galapagos Islands lie off the coast of South America, about 600 miles west of Ecuador. For most of history, the islands’ isolated location provided their native flora and fauna with a pristine environment in which to evolve and adapt, unfettered by outside influences. Though perhaps most famous as the natural laboratory for Charles Darwin’s groundbreaking work on adaption and natural selection, today these rocky volcanic isles are both a popular ecotourism destination and a setting for scientific research.
The Galapagos have 500 species of indigenous plants, 180 of which are endemic to the islands. Unfortunately, since the islands were first officially settled in the mid-1800s, more than 800 species of introduced plants have threatened many native species. Many islands have an arid climate populated largely by cacti. Species include the prickly pear (Opuntia spp.), giant candelabra cactus (Jasminocereus thouarsii) and lava cactus (Brachycereus nesioticus). Many coastal areas are home to mangrove swamps, in which black (Avicennia germinans), button (Conocarpus erecta), red (Rhizophora mangle) and white (Laguncularia racemosa) mangrove trees thrive. Other native or endemic plants include the Galapagos lantana (Lantana peduncularis), a dense shrub that blooms with white flowers; Galapagos peperomia (Peperomia galapagensis), a tiny, herbaceous perennial that produces green flowers and round drupes; and straight-spined lecocarpus (Lecocarpus lecocarpoides), a 3-foot-tall shrub that blooms with yellow, disc-like flowers.
Darwin’s theory of evolution stemmed largely from his observations of Galapagos birds. The omnivorous Galapagos mockingbirds (Nesomimus parvulus) eat lizards, fruit, insects and nest in trees and cacti. Mockingbirds live in groups and tend to show little to no fear of humans. Other native birds include the waved albatross (Diomedeidae irrorata), a rare seabird that only nests on Hood Island, and 13 species of finches (Geospizinae spp.) that populate the islands. Known as Darwin’s finches, these small birds all have different beak shapes and sizes that relate to their eating habits. One species, the woodpecker finch, uses tools; it uses twigs to dig for insects in the dirt.
The Galapagos are named for their largest animal resident, the Galapagos tortoise (Geochelone elephantopus). These huge tortoises weigh up to 500 pounds and live up to 150 years. The land iguana (Conolophus spp.) is endemic to the Galapagos. These large lizards live up to 60 years and weigh as much as 15 pounds. They eat fruit, shrubs and cactus pads. The small lava lizard (Tropidurus spp.) grows up to 1 foot long and is endemic to the Galapagos. These carnivores eat insects, snails and other lizards.
The Galapagos are home to several marine mammals, including the Galapagos fur seal (Arctocephalus galapagoensis). This endemic seal is pale brown and grows to about 5 feet long. Sea lions (Zalophus californianus wollebaeki) also live near the shore. They grow up to 6 feet long and eat fish, squid and octopus. The Galapagos are also home to the only ocean-going lizard, the sea iguana (Amblyrhynchus spp.). This sea-faring reptile searches for seaweed up to 50 feet underwater and grows up to 5 feet long.
Based in the Southwest, Linsay Evans writes about a range of topics, from parenting to gardening, nutrition to fitness, marketing to travel. Evans holds a Master of Library and Information Science and a Master of Arts in anthropology.