The first thing to know about the flora and fauna of the Galapagos Islands is the difference between Oceanic islands and continental islands. Continental islands are those which at some point in the past were connected to one of the major continents, by some sort of land bridge. This means that, because a continental island was connected to the continent, it will have flora and fauna that you would find on the continent. An oceanic island, on the other hand, was never at any time connected by any sort of land bridge to the continent. Oceanic islands are formed by underwater volcanoes, which over time rise to the surface. Volcanoes rise to the surface and become oceanic islands but don't bring any life with them. Flora and fauna which have excellent means of dispersal will eventually arrive on an oceanic island and, if conditions allow, it will thrive. There are basically three ways for living organisms to have arrived historically in the Galapagos Islands:

• floating on the ocean surface
• carried by the wind
• carried on or in the body of another organism who arrives by air or by sea

It's hardest for land animals to reach the Galapagos, since they are oceanic islands. Vertabrates are represented mainly by birds and reptiles. Amphibians and freshwater fish do not exist on the Galapagos because their means of dispersal are relatively difficult. There are very few mammals, and the only insects are butterflies and beetles, mainly. There are many land birds that are completely absent from the Galapagos as well.

In the plant world, ferns are well represented on the Galapagos Islands. So are grasses and sedges. There are no palm trees, and there are very few trees that are native to the islands. On the other hand, there are eleven species of orchids! Seeds that have an air pocket between the embro and the shell, such as legumes, can float very far very easily. There is also a species called the Galapagos cotton, or Gossypium darwinii, which can float for long periods of time in salt water. This species can float for up to ten weeks, and the Humboldt current can carry the seed from Peru in less than tims than that.

Animals that can float also have better chances of arriving in the Galapagos Islands...namely the turtle. There is a pocket of air between their back and the underside of their shell, so flotation is natural and easy for them. Other organisms arrive on the Galapagos by floating in the sea on rafts made of vegetation, which can drift for hundreds of miles, originating from coatal areas on the continent. Peru and Ecuador are sources of much life on the Galapagos through this method. Also, floating plam tree logs can carry insects to the islands. Logs have been known to float from Panama to the islands of the Galapagos at a rate of 75 miles a day. That means a log could reach Cocos Island in two weeks, carrying a reptile such as a boa constrictor. Creatures that make use of currents for passive transportation have also arrived and live on the Galapagos. Sea lions and fur sea lions arrived from California and the Antarctic, and colonized the Galapagos Islands in a giant group migration.

Birds have transported just about everything else to the Galapagos Islands. Seagulls usually arrive from continental areas full of much vegetation adn bring seeds with them. Seeds are carried in stomachs or in feathers of seagulls. Sceintists estimate that 59 percent of the 607 plant species in the Galapagos were transported there by birds. The rest was carried by wind (32 percent) and nine percent arrived via flotation on the sea.

Today, the flora and fauna of the Galapagos are some of the most unique and fascinating in the world. In fact, there are now species here, thanks to evolution, which exist nowhere else on earth.

Unique Organisma of the Galapagos Islands

Galapagos Penguin Galapagos dove some land iguanas some marine iguanas ginat tortoises Darwin's finches flightless cormorant waved albatross some mockingbirds lava gulls