Human hands manipulate tools, whale and dolphin fins are adapted for swimming and bird wings are adapted from flying.

One example is the pentadactyl limb which exists in a variety of species – mammals, birds, amphibians and reptiles all share a similar arrangement of bones in their appendages based on a five-digit limb. Selective breeding has shown that artificial selection can cause evolution – race horses, for example, have been bred for speed and are lighter, taller and quicker – these changes in traits and characteristics are examples of evolution.Īdaptive radiation is when organisms diversify from an ancestral species into many new ones – these species may have features that are similar in structure despite being used in different ways – these are homologous structures. (a) Homologous structures have similar morphology, embryology and anatomy, etc but are dissimilar in. We can see this by dating the fossils to find out when each sample was from. Register to Get Free Mock Test and Study Material. 10th Class Chemistry Notes 2023 Free Download. The fossil record shows that the features of organisms have changed over time. Download 12th Class Chemistry Unit 11 Solved MCQs From Past Papers: B).

and indirect evidence like footprints, tooth marks. Homology is the relationship between structures or DNA derived from the most recent common ancestor.

For IB Biology, there are three types of evidence for evolution you need to know: fossils, selective breeding and homologous structures.įossils are preserved remains or traces of organisms from the past – they include direct evidence like bones, teeth, shells, leaves etc.

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