Difference Between Homologous and Analogous (With Table)

The study of anatomy is one of the major topics in biology. It has several parts in it. Two of them are homologous and analogous structures of organisms. These topics might be often confusing for some to understand. But understanding them is one of the important concepts in anatomy.

Knowing the differences and the similarities between the organisms is important. In animals like cats and fish, or any others there are many distinctive differences. The reason that this knowledge is mandatory is that it helps scientists to get a better experience while studying the structures of different organisms without having being applied any dangerous experiments on them. In animals like cats and fish, or any others there are many distinctive differences.

Homologous vs Analogous

The difference between homologous and analogous is that structures of a homologous organism share an embryonic origin while organisms with analogous organs have identical functions. Basically, those animals having the features of similar functions are the homologous ones but they are identified as homologous ones only if they have a similar origin since their evolution.

A wing of a bat can be the most appropriate and classic example of a homologous structure. This is so because both of them have a similar structure of the bone, and being a mammal, the evolutionary structure of a bat is vividly similar. While the thing to keep in mind here is that the wing of a bat or even any other bird is used for flying but the hand of a human are usually used for lifting materials or any other task to perform but not to fly.

Analogous structures on the other hand are the ones that have features of totally different species but possess the same function. This is although not necessarily in the function the functionality is the same for the animals. These features are the ones that are not derived from an ancestor like the homologous ones but are evolved with time due to the common environmental challenges and aspects.

Comparison Table Between Homologous and Analogous

Parameters of ComparisonHomologousAnalogous
DefinitionHomologous are the ones that have a similar appearance in structure but the functions of those are different.Analogous are the ones that have different-looking structures but the functions are the same.
FunctionsHomologous have dissimilar functions.Analogous have similar functions.
InheritanceThese structures are inherited from common ancestors.The structures of analogous animals are not inherited from their ancestors.
SpeciesThe homologous feature is developed in related species only.Features are developed in the unrelated species
DevelopmentHomologous features are the development results of adapting to a different environment.Analogous features are the development results of adapting to a similar environment.

What is Homologous?

Talking generally, in general science homologous means something to show similarity between the two. Now the similarity can be in structure, function, feature, or characteristics. While understanding homologous in chemistry mean a series of molecules or particles that differ from each other due to continuous increment in them.

In general science, it is a concept of anatomy in the biology stream, which refers to the animals having the features of similar functions but the condition here is that they are identified as homologous ones only if they have a similar origin since their evolution. Morphology is the structural characteristics of an organism and it includes both external and internal features of the organism, from shape and color to bones and muscles. Now that particular study of internal parts is known as anatomy and homology is part of the anatomy.

What is Analogous?

The term analogous was derived from the Greek language from the word ‘analogous which exactly means- is according to the exact ratio or proportion. These analogous structures are the ones that are derived from different individuals of different species but serve the same function.

This can be explained with few examples. Humans’ brains and computers, both work the same way but are designed to be different and the structure varies from each other a lot. Another example would be the wings of a small bee and the wings of a hummingbird, here the structure, shape, size, and color of the wings of both the animals are different but the function served is absolutely the same which is to fly.

Main Differences Between Homologous and Analogous

  1. The main difference between homologous and analogous structure is their workings and what they are actually, Homologous are the ones that have similar appearance in structure but the functions of those are different while Analogous structures are the ones that have different looking structure but the functions of them are the same.
  2. Talking about the functions which differentiates them the most, Homologous have dissimilar functions but Analogous have similar functions.
  3. The structures of homologous creatures are inherited from common ancestors while the structures of analogous animals are not inherited from their ancestors.
  4. Not just this, the development of both the structures are different too, Homologous feature is developed in related species only while analogous features are developed in the unrelated species
  5. The environment in which these features are developed among the species is varies to, Homologous features are the development results of adapting to a different environment while the Analogous features are the development results of adapting to a similar environment.

Conclusion

It concludes now that homologous and analogous are two different parts of anatomy which is itself a stream of biology. These are different studies that specify various similarities and differences between many animals and other creatures. These topics might occur to be quite confusing to some but once understood, they are the most interesting ones. Their understanding helps scientists to understand the internals of an organism better and even discover their new features without having perform any dangerous experiments on them.

References

  1. https://academic.oup.com/sysbio/article-abstract/19/2/99/1655771
  2. https://www.annualreviews.org/doi/abs/10.1146/annurev.biochem.77.061306.125255
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