As a result of immunodeficiency, most infected cats do not show symptoms and have normal life expectancy, however they are prone to developing other infections and certain types of cancer. A retrovirus, such as FIV, inserts a copy of its genetic material into the DNA of a host cell, where it can replicate. FIV is a lentivirus. a specific type of retrovirus that can take months, or even years to incubate, so the virus is slow moving, capable of lying dormant in the body before causing symptoms.
A fossil is the remains or traces of a once-living plant or animal that was preserved in rock or other material before the beginning of recorded history.The term also is used to describe the fossil fuels (oil, coal, petroleum, and natural gas) that have been formed from the remains of ancient plants and animals.nother type of fossil is the darkened carbon imprint of a buried plant or, more rare, animal. When an organism dies and is buried, pressure underneath Earth's surface compresses the organism between rock faces.
Fossils are most often preserved within sediments that were deposited in water, such as wetlands, river basins, or the ocean. Permineralization or Petrification-After an organism is buried, minerals carried by water such as silica, calcite or pyrite replace the organic material in the fossil.he oldest fossils in the fossil record date from 3.5 billion years ago, however it wasn't until around 600 million years ago that complex, multi-cellular life began was first preserved in the fossil record. There are two main types of fossils; body and trace.