Galapagos - Netflix
Wed 19 June 2019
Natural history series exploring the Galapagos Islands, which lie 1,000 kilometres off the coast of South America.
Runtime: 60 minutes
Galapagos - Darwin's finches - Netflix
Darwin's finches (also known as the Galápagos finches) are a group of about fifteen species of passerine birds. They are well known for their remarkable diversity in beak form and function. They are often classified as the subfamily Geospizinae or tribe Geospizini. They belong to the tanager family and are not closely related to the true finches. The closest known relative of the Galápagos finches is South-American Tiaris obscurus. They were first collected by Charles Darwin on the Galápagos Islands during the second voyage of the Beagle. Apart from the Cocos finch, which is from Cocos Island, the others are found only on the Galápagos Islands. The term “Darwin's finches” was first applied by Percy Lowe in 1936, and popularised in 1947 by David Lack in his book Darwin's Finches. David Lack based his analysis on the large collection of museum specimens collected by the 1905–06 Galápagos expedition of the California Academy of Sciences, to whom Lack dedicated his 1947 book. The birds vary in size from 10 to 20 cm and weigh between 8 and 38 grams. The smallest are the warbler-finches and the largest is the vegetarian finch. The most important differences between species are in the size and shape of their beaks, which are highly adapted to different food sources. The birds are all dull-coloured. A long-term study carried out for more than 40 years by the Princeton University researchers Peter and Rosemary Grant has documented micro-evolutionary changes in beak size affected by El Niño/La Niña cycles in the Pacific.
Galapagos - Species - Netflix
Genus Pinaroloxias Cocos finch (Pinaroloxias inornata)
Medium ground finch (Geospiza fortis) Small ground finch (Geospiza fuliginosa) Large ground finch (Geospiza magnirostris) Common cactus finch (Geospiza scandens)
In 1981, a male Española cactus finch arrived at Daphne Major island. Its mating with local Galapagos finches has produced a new population that can exploit previously unexploited food due to its larger size. They do not breed with the other species on the island, as the females do not recognize the songs of the new males. Genetic evidence shows that now, after two generations, it lives in a complete reproductive isolation from the native species. According to professor Leif Andersson of Uppsala University, a taxonomist not aware of its history would consider it a distinct species.
Genus Geospiza Española cactus finch (Geospiza conirostris) Sharp-beaked ground finch (Geospiza difficilis) Vampire finch (Geospiza difficilis septentrionalis)
Genus Platyspiza Vegetarian finch (Platyspiza crassirostris)
Galapagos - References - Netflix