The main difference between homology and convergent evolution is that homology is the evolution of the similar structures in species evolved from a recent common ancestor whereas convergent evolution is the independent evolution of similar structures in unrelated organisms. Furthermore, homology develops homologous structures while convergent evolution develops analogous structures. Moreover, homologous structures have similar structures but, different functions while analogous structures have different originations of structures but, similar functions.
Homology and convergent evolution are two mechanisms, which develop similarities in anatomical structures. Generally, they are two of the evidence of evolution.
Key Areas Covered
1. What is Homology
– Definition, Characteristics, Examples
2. What is Convergent Evolution
– Definition, Characteristics, Examples
3. What are the Similarities Between Homology and Convergent Evolution
– Outline of Common Features
4. What is the Difference Between Homology and Convergent Evolution
– Comparison of Key Differences
Key Terms
Anatomical Structures, Convergent Evolution, Evolution, Homology
What is Homology
Homology is the development of similar anatomical structures in species with common ancestry. Significantly, these structures occur as a result of divergent evolution. Generally, divergent evolution is responsible for the development of less similar structures in function-wise due to the adaptations to the changes in the environmental conditions over time. Also, environmental changes can occur due to the migration of species to new climates, their competition for niches or even due to the genetic changes such as mutations, occurring as a result of microevolution. However, although these structures have different functions, they have similar anatomy.
Figure 1: Darwin’s Finches
Furthermore, Darwin’s finches are one of the most classical examples of divergent evolution. Here, several different finches share a common ancestor but live on varying diets but, have different shapes of beaks corresponding to their diet. typically, divergent evolution is exhibited when two populations are separated from a geographical barrier. Significantly, this causes either allopatric or peripatric speciation.
What is Convergent Evolution
Convergent evolution is the opposite pattern of evolution to divergent evolution. significantly, the main difference between convergent and divergent evolution is that convergent evolution is the development of similar anatomical structures in several species that live in the same environment. Therefore, their function of that particular structure is similar. However, it may have different phenotypical and genotypical origins. Generally, this type of structures with similar function but, different anatomy is known as analogous structures.
Figure 2: Analogous and Homologous Limbs
Moreover, one of the main classic examples of convergent evolution is the recurrent evolution of flight in pterosaurs, bats, birds, and insects. In addition, the camera eye of vertebrates including mammals, cephalopods including squid and octopus, and cnidarians including jellyfish is another example of convergent evolution.
Similarities Between Homology and Convergent Evolution
- Homology and convergent evolution are two mechanisms, which develop similar anatomical structures either structure-wise or function-wise.
- Both are evidence of evolution.
- They derive as adaptations to the changes in the environment.
Difference Between Homology and Convergent Evolution
Definition
Homology refers to the existence of shared ancestry between a pair of structures or genes in different taxa while convergent evolution refers to the independent evolution of similar features in species of different periods in the timeline.
Ancestry
Homology is the evolution of similar structures in species evolved from a recent common ancestor whereas convergent evolution is the independent evolution of similar structures in unrelated organisms.
Type of Evolution
Homology is a type of divergent evolution while convergent evolution is the opposite form of divergent evolution.
Types of Structures
Homology develops homologous structures while convergent evolution develops analogous structures.
Significance
Homologous structures have similar structures but, different functions while analogous structures have different originations of structures but, similar functions.
Genetic Similarities
Homology has a high degree of genetic similarity while convergent evolution does not develop any genetic similarity.
Occurrence
Homology occurs as a result of evolutionary relationships while convergent evolution occurs as an adaptation in response to the changes in the environment.
Examples
Darwin’s finches are an example of homology while the wings of birds, bats, and insects are an example of convergent evolution.
Conclusion
Homology is the development of similar anatomical structures species with common ancestry. Significantly, although these structures are homologous structures, which are similar in anatomy, they have different functions. However, they exhibit a significant level of genetic similarity. In contrast, convergent evolution is the independent development of similar anatomical structures in unrelated species. Generally, they are analogous structures, which perform similar functions as they develop as adaptations in response to the environment. On the other hand, these structures have no genetic similarities. Therefore, the main difference between homology and convergent evolution is the type of structures develop in each type of evolution.
References:
1. “Homologies and Analogies.” Understanding Evolution, Available Here.
Image Courtesy:
1. “Darwin’s finches” By John Gould (14.Sep.1804 – 3.Feb.1881) – From “Voyage of the Beagle” (Public Domain) via Commons Wikimedia
2. “Analogous & Homologous StructuresAnalogous & Homologous Structures” By Vanessablakegraham – Own work (CC BY-SA 4.0) via Commons Wikimedia
Leave a Reply