Question

Consider a group of bacteria that you are trying to classify as either the same species or different species. They are morphologically identical, reproduce by binary fission but live in slightly different environments. Which species concept(s) could be applied to these organisms?

Select All that Apply.

A) Binomial

B) Morphological

C) Phylogenetic

D) Ecological

E) Biological

I have my assumptions but I wanted to some input on this. Please explain your reasoning for all selections and for those that you opt not to select

My Thoughts:

species are identified using the criterion of reproductive isolation.

In different species, individuals do not interbreed in nature or do not produce viable or fertile offspring when mating takes place. This would include the different ecological barrier and thus the biological as well.

Same species would include individuals that are are actually or potentially interbreeding or the individuals are reproductively isolated from other groups. They are morphologically identical which means you must take that species concept into account.

Lastly phylogenetic would be an easy DNA test.

However am I wrong in assuming this? Because aren't asexual bacteria an exception to the biological species concept or something? But it cant be nothing. So i am at a crossroads lol

Answer 1

Binomial system consists of assigning a generic name and specific epithet to the bacteria. It can be used for bacterial species.

The morphological species concept is based on the morphological differences among organisms. For plants and animals, this is a widely used species concept as it simple to use and has wide applicability.

However with respect to bacteria, it is not very useful as these organisms are too simple in terms of their morphology.

Phylogenetic classification involves the use of molecular sequencing techniques, defining patterns of ancestry.

This method can be applied to all kinds of organisms, including bacteria.

The ecological species concept identifies and characterizes the species in terms of its ecological niche. It focuses on the unique adaptations in a biological community in terms of feeding behavior, mode of nutrition or spatial roles. These can be applied to bacteria.

According to the ‘Biological Species Concept’, speciation is said to occur when separated population are unable to exchange genetic material by interbreeding. They cannot interbreed even if they are eventually brought back together. Only those plants and animals that can produce fertile and viable offspring with other members of its species come under the biological species concept.

Since bacteria produce both sexually and asexually, the concept of biological species cannot be applied here.