Here. Amazing what sheer randomness can do.
It has been known since the 1970s that E. chloritica “steals” chloroplasts from V. litorea (called “kleptoplasty”) and embeds them into its own digestive cells. Once inside the slug cells, the chloroplasts continue to photosynthesize for up to nine months–much longer than they would perform in the algae. The photosynthesis process produces carbohydrates and lipids, which nourish the slug.
How the slug manages to maintain these photosynthesizing organelles for so long has been the topic of intensive study and a good deal of controversy. “This paper confirms that one of several algal genes needed to repair damage to chloroplasts, and keep them functioning, is present on the slug chromosome,” Pierce says. “The gene is incorporated into the slug chromosome and transmitted to the next generation of slugs.” While the next generation must take up chloroplasts anew from algae, the genes to maintain the chloroplasts are already present in the slug genome, Pierce says.
“There is no way on earth that genes from an alga should work inside an animal cell,” Pierce says. “And yet here, they do. They allow the animal to rely on sunshine for its nutrition. So if something happens to their food source, they have a way of not starving to death until they find more algae to eat. “
Maybe the Darwin lobby can get an injunction in some U.S. court against the slugs for violating the law that Darwinian natural selection acting on random mutations is responsible for creating all or most changes in life forms.