is the chronicle of evolution over millions of years of geologic time engraved in the order which fossils appear in rock strata.

Explanation:

Fossils can be defined as the evidence of pre-historic life. Fossils are usually found buried deep inside the earth in the strata of the sedimentary rocks. The process of formation of fossils is called fossilization. The preservation of fossils can occur in two forms -as impressions and as petrifaction.

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.

thrombocytopenia, which is a deficiency in blood platelets, can cause bleeding and bruising in the dermis similar to senile purpura. other possible causes include: exposure to ultraviolet rays and aging skin are common causes of senile purpura. senile purpura may also be a sign of collagen loss in the skin and bones.