MADAGASCARP: A LAND WITH A WILD” GEOLOGIC HISTORY” AND ASSOCIATED LIFEFORMS

MADAGASCAR: Part 1--Geologic History Summary 

  Part 2 = examples of flowers and Part 3 = examples of animals (will soon follow).

170 million years ago Madagascar was part of a giant landmass, comprised of Africa, South America, Africa, India, Antarctica, and Australia.

135 million years ago, Madagascar and India were still united but separate from the other landmasses mentioned above.

88 million years ago, Madagascar began to separate from India.

60 million years ago, Madagascar was finally and totally ISOLATED and has been ever since [note: Madagascar is about 78 percent the size of Texas].

The present-day geology of Madagascar is evidence of a complex history. The central and eastern parts of this land consist of metamorphic and igneous rocks, including Precambrian-age granite. In stark contrast, the western part consists of fossil-bearing sedimentary rocks ranging from Carboniferous to Tertiary-age rocks (e.g., Madagascar is well known for its Cretaceous ammonites). As a result of this complicated geologic history, the animals and plants that have lived in Madagascar have had significant time and opportunity to evolve into many new groups. 

Approximately 83 percent of its Madagascar’s flower species are not found elsewhere on Earth. Approximately 85 percent of Madagascar’s animal species are not found elsewhere on Earth. Also, Examples of some of these flowers and animals will be shown and briefly discussed in my next two upcoming posts. 

Figure 1. Google Earth satellite view of southern Africa (on the left) and Madagascar (on the right).

Figure 2. Google Earth satellite view of Madagascar.