Fossils, although technically they are not preserved in the earths crust; the minerals in the bones and pore spaces have been replaced by other harder minerals which take much longer to weather.
There are a number of different fossilization processes. See this link :
How are Fossils Formed?
Interphase
replication
There are 23 pairs of chromosomes in a normal human body which means 46 chromosomes. People with down's syndrome have 47 chromosomes.
poles
parthenogenesis