What is the euglena able to do that other protists cannot?

Euglena is a protist that exhibits both plant and animal characteristics, therefore they have the ability to live a double life. When there is sufficient sunlight, they are green and photosynthetic like plants and they can make their own food. They use their chloroplasts to produce sugars by photosynthesis. Also, in the absence of sunlight, when they cannot produce their food, they consume smaller living organisms such as amoeba like the animals.