Brain size has increased nearly 3x in 4 million years.
Answer:
1- Presence of phenotypic variation
2- some phenotypic variation due to genetic variation
3- the given trait has an impact on fitness
Explanation:
The evolutionary theory by natural selection proposed by Darwin in his publication “On the origin of species” (1859) is based on a series of assumptions that enable to understand the amazing biodiversity on the Earth. First, individuals are not identical among them, i.e., there exists variation in the traits among the members of a given population, species, etc. Second, phenotypic variation leads to differential survival and reproduction of the organisms that are best fitted to the environment (i.e., competence among the members of the population). Finally, phenotypic traits are passed from generation to generation (i.e., phenotypic variation is inheritable), thereby favoring offspring from parents more adapted to the environment.
The answer is C Heterozygous
Explanation: the inability to roll your tongue is a recessive trait. Since both parents are heterozygous, they carry that recessive gene, so their child will have a 25% chance of having that recessive trait; and therefore, unable to roll their tongue.
I believe the answer is d, periodic time line
The muscular system allows for movement within the body, for example, during digestion or urination. Smooth muscles in the gastrointestinal or GI tract control digestion. The GI tract stretches from the mouth to the anus. Food moves through the digestive system with a wave-like motion called peristalsis.