1) Endosymbiotic event 
Kleptoplasty or kleptoplastidy is a symbiotic phenomenon whereby plastids, (notably chloroplasts), from algae are sequestered by host organisms. The word is derived from Kleptes (κλέπτης) which is Greek for thief. The alga is eaten normally and partially digested, leaving the plastid intact. The plastids are maintained within the host, temp...