Among the pre-historic species associated with the LA BERA TA PITS are pleitocene ,dire wolves ,short faced bears, ground sloths, and the stste fossil of california, the saber-toothed cap..... i hope it will help you.... :)
A specific protein called a receptor
First, a complete digestive system means that the digestive tract has a beginning or the oral end and the opposite end or the aboral end. This is found in more complex animals starting from roundworms (flatworms have an incomplete digestive tract). A closed circulatory system is found in animals more recent than mollusks. The presence of the coelom makes it more evolved than the flatworms.
Specifically, a small animal with a segmented body, short stiff appendages, and soft skin with the above characteristics point out to the phylum Annelida or annelids.