Why would an organism benefit from undergoing more than one

Why would an organism benefit from undergoing more than one endosymbiont event throughout evolution? Give an example to support your argument?

Solution

The debate over \"red lineage\" in diatoms and other algae that got chloroplasts via red algae, dominate marine ecosystems more than any other algal group.

Some propose that the successors descend from unrelated organisms that engulfed red algae at different times. This view is based on a greater apparent diversity of the red lineage as compared to other groups, and also on a finding that red algal chloroplasts contain more genes critical to their own functioning than other algal types, which might have helped them successfully invade multiple organisms.

According to some other researchers, these algae share genetic traits beyond their distinctive chloroplasts: that the red lineage is monophyletic and stems from just one secondary endosymbiont event.