Many rickettsia are PATHOGENS.
Pathogens are micro organism that cause diseases and rickettsia are majorly disease causing organisms. They are rod shaped bacteria and most species are gram negative. They are natural parasite of some arthropods and they cause diseases in both humans and animals.
Answer:
Phenotypic changes:
When Rhodobacter is cultured in total darkness for multiple generations, the ability to produce it's own photopigment reduces with time with little or no ability to undergo its own photosynthesis due to absence of enzymes or pigment for photosynthesis.
It becomes expensive for the Rhodobacter to undergo photosynthesis. This allows mutants that can grow in the dark to take over from the culture grown in the dark.
Evolutionary processes:
It's natural selection that allows the fittest organism to survive. As in the case of the mutants
A) a slight decrease in the use of public transportation throughout the country.
1,bc the prefix auto=self, like in the word autobiography, where this can be translated into self-biography, or self-writing