evidence of evolution

• fossils are the preserved remains of plants and animals whose bodies were buried in sediments
• the word fossil is derived from the latin fossillis meaning unearthed
• preserved evidence of the body parts of ancient animals, plants, and other life forms are called body fossils
• trace fossils are the evidence left by organisms in sediment, such as footprints, burrows, and plant roots.
• petrification, compression, molds and casts, and preserved remains are the four main ways of describing fossil preservation
• petrification is the process by which organic matter exposed to minerals over a long period of time is turned into a stony substance
• compression happens when a dark imprint of fossil is produced as a result of high-pressure forces exerted by the weight of overlying sediments and perhaps sea water
• plant leaves and ferns are good examples of fossils produced by compression
• mold and cast formation occurs when an object decays or dissolves leaving behind its shape
• soft- bodies sea creatures such as snails are commonly found as molds and casts because their shells dissolve easily
• preserved remains are the rarest form of fossilization.. it preserves original skeletons and soft body parts
• a fly and spider trapped in amber is an example of a preserved remains in fossils
• the evidences of evolution are: fossils, comparative anatomy, comparative embryology, and vestigial structures
• comparative anatomy is the study of similarities and differences in the structures of different species . similar body parts may be homologous structures or analogous structures
• homologous structures are structures that are similar in related organisms because they were inherited from a common ancestor. these structures may or may not have the same fuction in the descendants
• human, cheetah, whale, and bat are examples of homologous structures
• analogous structures are structures that are similar in unrelated organisms. the structures are similar because they evolved to do the same job, not because they were inherited from a common ancestors
• bat, bird, and butterfly are examples of analogous structures
• Comparative embryology is the study of the similarities and differences in the embryos of different species.
• vestigial structures are structures that have lost their function but are still present in the body. for example, the appendix
• there are two types of fossils - trace fossils (footprints) and body fossils (bones)