it is both

their sail like fins are to help them with body temperature

You could be talking about spinosaurus, which had a large fan shaped portrusion coming out of its back, or you could be talking about the permian early reptiles, dimetrodon and edaphosaurus. Neither of which were dinosaurs.

Pelycosaurs were primarily carnivores, eating meat as their primary food source, and many were high level predators in the food chain scientists believe. But a few, such as Edaphosaurus, were also believed to have also eaten a diet of plants in addition to meat. And the Cotylorhynchus was believed to be a true herbivore, eating only plants. So, the Order Pelycosauria contained creatures that ate a little bit of everything.

(2+2)/(2+2)=1

(2/2)+(2/2)=2

(2*2)-(2/2)=3

(2+2+2)-2=4

(2+2)+(2/2)=5

(2*2*2)-2=6

((2-.2)/.2)+2=7

2+2+2+2=8

(22/2)+2=9

((2+2)*2)+2=10

((2-.2)/.2)+2=11

(2+2+2)*2+=12

(22/2)+2=13

(2/.2)+(2+2)=14

2+(2/2)/.2=15

(2+2)*(2+2)=16

...??????????=17

((2+2)/.2)-2=18

((2+2)-.2)/.2=19

22- √(2+2)=20