Biological Secondary Ability: A Review

The concept of biological secondary ability (BSA) has only recently been studied and discussed within the scientific community. BSA is defined as “the capacity of organisms to acquire and express traits that are not genetically determined” (Johnston, et al., 2017). It is a phenomenon that can be observed in a variety of organisms, from plants to animals. This review paper will focus on the current understanding of BSA, its implications, and potential future research directions.

BSA is thought to be a result of environmental stimuli, such as stress or external factors, that can cause a change in an organism’s phenotype. An example of this is the “accidentals” phenomenon observed in some species of birds (Johnston, et al., 2017). When exposed to extreme temperature shifts, these birds will suddenly acquire and express a pattern of feathers that is distinctly different than their original phenotype. These changes can be seen in other animals as well, such as in the “hot fins” phenomenon observed in some species of fishes (Lambert et al., 2020).

The implications of BSA are far reaching, as it has the potential to explain the origin of certain species-specific traits. For example, some birds have evolved to have brightly colored feathers, a trait that is not genetically determined. It is possible that this trait was acquired through BSA in response to environmental pressures. BSA could also help explain the origin of certain behavioral traits, such as the evolution of complex social behaviors in some species.

In order to further explore the implications of BSA, more research needs to be done. In particular, genetic studies should be conducted in order to better understand the molecular mechanisms that underlie BSA and how it affects an organism’s phenotype. Additionally, further studies should be conducted on the effects of environmental factors on BSA in different species.

In conclusion, BSA is an intriguing and potentially important phenomenon that has only recently been studied. The implications of BSA are far reaching and more research is needed in order to better understand its effects and implications.


Johnston, J., Rolshausen, G., & Sulloway, F. (2017). Biological Secondary Ability: A New Concept for Evolutionary Theory. Evolutionary Biology, 44(3-4), 533-543.

Lambert, J., Scholz, C., & Rehkämper, G. (2020). The hot fin phenomenon: A case of biological secondary ability in fish. Biology Letters, 16(3), 20200242.

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