to an evolutionary biologist fitness simply means reproductive success and reflects how well an organism is adapted to its environment.We call them fit because of how successfull they reproduce not how well they do at athletic events
The term "fitness" in evolutionary biology means the ability of an organism to pass on its genetic material to its offspring. Biological or "Darwinian" fitness is being able to live long enough to reproduce and keep the population or species alive.
Psychrotrophs are those bacteria which can tolerate cold temperature and have optimum growth above 15 degree Celsius.
Halophiles prefer high salt concentration.
Mesophiles prefer temperatures with a average of 37 degree Celsius.
Anaerobes grow in absence of oxygen.
In the given experiment, none of the bacterial cultures were placed in saline or anaerobic conditions. So, the bacterial species is not an anaerobe or halophile.
Again the cultures did not show growth at 37 degree celsius so they are not mesophiles.
Maximum growth at 22 degree celsius and a little growth in refrigerator make it obvious that the species is a Psychrotroph.
