The term Analogous organ Is used to refer to multiple structures in different species that have the same function but have evolved differently. That is why they do not share a common ancestor.
The analogous organs show how different species have evolved to become similar organisms. The analogy is not limited to the appearance as it can include the behavior as well.
Bird and insect.
These organs are the opposite to homologous organs, which refer to structures that show a similar morphology and anatomy but which have distinct functions.
The analogous organs are applied in reference to the concept of convergent evolution. This means that they belong to the evolutionary process where organisms evolve parts of the body that are analogous in terms of structure and function, regardless of their ancestors.
Examples of similar structures are the wings of insects and the wings of birds, which are used to fly; The articulated legs used for the movement of insects and vertebrates; Or the fins of the fish and the fins of the whales.
These analogous organs show that they have the same function, as for example to fly or to move, but they have a different origin or they have evolved separately.
List of some analogous organs found in organisms
Wings of birds and insects
A wing is a type of flap that produces a lift, while moving through the air or some other fluid. For this reason, the wings have sections which are subject to aerodynamic forces and act as aerodynamic profile.
In nature, wings have evolved in dinosaurs, in birds, in mammals, in fish, in reptiles and in plants as a means of movement.
Several species of penguins and other flying or non-flying water birds use their wings to propel themselves through the water.
Many flying animals, like bats, birds and insects have wings. However, although these wing structures have the same function for these animals, bony structures, wing covers (such as feathers, scales, hair, etc.), sizes and shapes are quite distinct.
For example, the wings of a butterfly and the wings of a bird superficially are similar in structure and have the same function. However, they have evolved independently for adaptation to the same function, such as for example flying.
This is because the analogous organs evolve thanks to their convergent evolution when the different organisms adapt to the same environment; Both do the same but they evolved separately.
The wings are a classic example of convergent evolution, since the pectoral members of the pterosaurs, the birds and the bats evolved in independent ways becoming wings to fly.
Fins
Another example of analogy is the fins of fish and penguins. In both cases, these organs help these animals to navigate in their natural environments.
Since one is a bird and the other is a fish, it clearly suggests that the development of the fins in both species is an adaptation to the similar environment they inhabit.
A fin is a thin component or an appendage attached to a larger body. The fins typically act as sheaves that produce lift or thrust. They also have the ability to direct or stabilize a movement by traveling in water, air, or any other fluid medium.
The fins first evolved in fish as a means of movement. The fins of the fish are used to generate momentum and control the subsequent movements.
Fish, and other aquatic animals such as cetaceans, actively propel themselves to their pectoral fins and tails.
When these marine animals with fins swim, they use other fins, such as their dorsal and anal fins, to achieve stability and refine their maneuvers.
Energy storage strategies in potatoes and potatoes
The strategy of energy storage between potatoes and sweet potatoes varies. The potato is an underground stem and the sweet potato is an underground root.
The potato is a modified stalk intended for food storage. For its part, the sweet potato is a root also modified for food storage.
Both the sweet potato and the sweet potato have edible parts that are similar organs. This happens because the organ of storage of the potato is in its stem, whereas the one of the sweet potato is in the root.
These organs are similar in function, but have different structural details, so they are analogous.
Sugar Petauro and Flying Squirrels
These two animals can glide in the air using their gliding wings. Both species are different in many ways: flying squirrels are mammals of placentas, while sugar petauros are marsupial mammals such as kangaroos.
To adapt to a common function, the flying squirrel and the sugar petauro evolved similar flying wings.
African cacti and euphorbias
Many African cacti and euphorbias are similar in appearance. Both are succulent, thorny, store water and adapt to desert conditions.
However, these plants belong to different families although they share common attributes according to the similar environmental conditions in which they are found.
Eyes of an octopus and a human
The eye of a human is very similar in structure to the eye of an octopus. However, the octopus and the human are not closely related and reside quite far from each other in the phylogenetic tree of life.
Moreover, the octopus eye is superior to the human eye since it does not have a"blind spot"like the human eye. Structurally, that is the only difference between the eyes even though they are quite genetically separated.
References
- Potato and sweet potato are analogous (2015). Recovered from meritnation.com
- Homology and analogy. Retrieved from amrita.olabs.edu.in
- Analogous structures in Animals and nature (2017). Retrieved from thoughtco.com
- Wing. Retrieved from wikipedia.org
- Analogous structures: definition & examples in Chapter 32. Retrieved from study.com
- Analogous structures in Definition. Retrieved from biology-online.org
- Analogous structures. Retrieved from explainry.com.