- Such mutations may result in functional Changes to the proteins encoded by the genes, or even the evolution of novel genes and proteins.biochemical evolution (molecular evolution) The changes that occur at the molecular level in organisms over a period of time. These range from deletions, additions, or substitutions of single nucleotides, through the rearrangement of parts of genes, to the duplication of entire genes or even whole genomes. Such mutations may result in functional changes to the proteins encoded by the genes, or even the evolution of novel genes and proteins.
- Biochemical evolution (molecular evolution) The changes that occur at the molecular level in organisms over a period of time. These range from deletions, additions, or substitutions of single nucleotides, through the rearrangement of parts of genes, to the duplication of entire genes or even whole genomes.
- Biochemical evidence of evolution is based on the fact that certain enzymes and chemical processes are found in the cells of all or nearly all life on Earth.
- It is the opposite of divergent evolution, where related species evolve different traits. … An example of convergent evolution is the similar nature of the flight/wings of insects, birds, pterosaurs, and bats. All four serve the same function and are similar in structure, but each evolved independently.
- In divergent evolution, two or more distinct species share a common ancestor from which they diverged. … They share a common ancestor and yet evolved into two different species. Another example is the dog, the wolf, and the fox
- shows the three main types of evolution: divergent, convergent, and parallel evolution.
people hear the word “evolution,” they most commonly think of divergent evolution, the evolutionary pattern in which two species gradually become increasingly different. This type of evolution often occurs when closely related species diversify to new habitats. On a large scale, divergent evolution is responsible for the creation of the current diversity of life on earth from the first living cells. On a smaller scale, it is responsible for the evolution of humans and apes from a common primate ancestor.
Convergent evolution causes difficulties in fields of study such as comparative anatomy. Convergent evolution takes place when species of different ancestry begin to share analogous traits because of a shared environment or other selection pressure. For example, whales and fish have some similar characteristics since both had to evolve methods of moving through the same medium: water.
Parallel evolution occurs when two species evolve independently of each other, maintaining the same level of similarity. Parallel evolution usually occurs between unrelated species that do not occupy the same or similar niches in a given habitat.
- There are several circumstances that can result in convergent evolution. Often, convergence occurs when organisms are required to adapt to similar environmental conditions, such as in the evolution of thick water-retaining leaves and spines on cacti and Euphorbia species, which are adapted to tolerate conditions of extreme drought but are native to separate continents. It may also occur when two different organisms occupy a similar niche, for example, the cryptic green coloration of Emerald Tree Boas (Corallus caninus) from South America and Green Tree Pythons (Chondropython viridis) from Australia, both of which live high up in the canopy of similar rainforests and occupy a niche predating upon birds.
- Convergence of life cycle and behavioral traits, such as the similar social colony structures between Naked Mole-rats (Heterocephalus glaber) and many species of social bees and ants, can also take place in order to maximize breeding success of individuals and within colonies. On a molecular level, the independent evolution of proteins and toxins has also occurred throughout many separate phyla; for example, sea anemones (Cnidaria), snakes (Vertebrates), scorpions (Arthropods) and cone snails (Molluscs) all produce neurotoxins which act similarly upon the neurotransmitter receptors of their prey.
- Convergent evolution can also arise through mimicry complexes, in which organisms evolve to replicate the morphology of other species. This adaption benefits the mimic either by way of protection when imitating the phenotype of an organism that is toxic or otherwise dangerous (Batesian mimicry), or allowing the mimic to exploit a resource or interaction by being mistaken for the model (Müllerian mimicry).
- A widespread example of convergent evolution is the evolution of wings and powered flight in birds, bats and (now extinct) pterosaurs, each of which belong to a different class of organism and therefore have very distant common ancestors.
- Fossil evidence has determined that flight evolved in pterosaurs (flying reptiles of the late Triassic period) around 225 mya and in birds around 150 mya, while mammalian bats evolved wings around 50-60 mya. The evolution of powered flight has only happened once in each of these lineages, although there are certain organisms, for example, ostrich birds, which have subsequently reverted back to being flightless while retaining their wing structures.