Lithosphere

Hayato IshidaIB Environmental

System SL P.1

Earth cross section 1. Crust2. Mantle3. 　 a- Outer core 　 b- Inner

core

4. Lithosphere5.

Asthenosphere

Inside the Earth

Plate tectonics theory Lithosphere → broken up into tectonic plates.

composed of both continental and oceanic crust.

Describes the large scale motions of Earth's lithosphere ride on the denser asthenosphere.

Eight major and many minor plates

Plate tectonics

•Some plates are a. moving toward each other, b. moving away, c. sliding past each

other.

Theory of continental drift

the movement of the Earth's continents relative to each other.

Influenced disjunct distribution

•evolution•biodiversity

Disjunct distribution

•Madagascar has a highly endemic biota.•Madagascar and India were the first land masses to split from Gondwanaland 160-120 million years ago.•India and Madagascar separated about 88-63 million years ago.•India collides with south Asia about 50 million years ago.•Recent molecular phylogeny supports that dispersal was a major factor in the formation of the Malagasy biota, and not vicariance.

-Sample of Madagascar

Animals in Madagascar

•Lemurs evolved in Madagascar

•Chameleons originated in Madagascar and dispersed to Africa, India and the Indian Ocean islands.