(genetics). (1) (Of, or pertaining to) An allele or a gene that is expressed in an organism âs phenotype, masking the effect of the recessive allele or gene when present. (2) (Of, or pertaining to) An organism that expresses the dominant gene (or allele).
Triceratops was a species of herbivorous dinosaur. Triceratops lived during the Mesozoic Era, during the days of the late Cretaceous period. A large herbivorous dinosaur, Triceratops grazed on plants and relied on its horns and frilled head for defense, cutting away at plants with its sharp beak. were larger relatives of the Chasmosaurus. They appear in Ice Age: Dawn of the Dinosaurs, The Triceratops are shown very briefly, wading through a pond.
Trilobites were the dominant species during the Cambrian Period, 540 to 490 million years ago. The Cambrian Period is the first geological time period of the Paleozoic Era (the âtime of ancient lifeâ). This period lasted about 53 million years and marked a dramatic burst of evolutionary changes in life on Earth, known as the Cambrian Explosion..