Maybe reading a textbook on biology and evolution could help, just a suggestion.
This is pretty humorous because the theories keep changing. A lot of schools are using textbooks with material that has been discounted by leading evolutionists, because by the time it prints and distributes an assumption of the theory has changed, but they will keep teaching it because that is in their textbook, and until new ones are obtained you need to keep teaching the outdated version because there is no other version available to the students. The evolution of the horse being a good example. Yup just go pick up a textbook and learn about Piltdown man and Lucy and the horses they rode.
Evolution has stood for one hundred and fifty years of challenges. You may be confused between the fact of evolution and the theory related to its mechanisms and means....some of which may be modified or dropped as new information emerges from research.
Something provides evidence for evolution when it demonstrates a change in characteristics from an ancestral form
Fossil Record
A fossil is the preserved remains or traces of any organism from the remote past
Fossil evidence may be either:
Direct (body fossils): Bones, teeth, shells, leaves, etc. Indirect (trace fossils): Footprints, tooth marks, tracks, burrows, etc.
Types of Fossils
The totality of fossils (both discovered and undiscovered) is known as the fossil record
The fossil record reveals that, over time, changes have occurred in features of organisms living on the planet (evolution) Moreover, different kinds of organisms do not occur randomly but are found in rocks of particular ages in a consistent order (law of fossil succession) This suggests that changes to an ancestral species was likely responsible for the appearance of subsequent species (speciation via evolution) Furthermore, the occurrence of transitional fossils demonstrate the intermediary forms that occurred over the evolutionary pathway taken within a single genus
Biogeography
Biogeography describes the distribution of lifeforms over geographical areas, both in past and present times
Biogeographical distribution supports the theory of evolution as it is found that closely related species are usually found in close physical proximity to one another, and that fossils from these regions resemble modern organisms
This suggests that these species share a common lineage (if speciation was random, distribution would be expected to be scattered)
Comparative Anatomy
A comparison of the anatomic features of different species provides further evidence of evolution
The presence of homologous structures and shared embryonic development between species indicates descent from common ancestors The presence of analogous structures and vestigial organs highlight the role of environmental influences in the process of natural selection
Homologous Structures
Homologous structures possess a similar underlying anatomy as a result of a shared evolutionary origin, but have evolved into a variety of distinct forms due to the presence of different selective pressures
Analogous Structures
Analogous structures are adaptations that possess similar features and functionality as a result of exposure to a common selective pressure, but have different underlying anatomies due to having unrelated evolutionary origins
Vestigial Organs
Some organisms show the presence of functionless and reduced remnants of organs that were once present and functional in their ancestors
Changes to the environment have rendered these organs redundant and so over time they have lost their functionality
Molecular Evidence
Molecular evidence involves identifying conservation in DNA and protein sequences as a basis for determining evolutionary relationships
