Conventional wisdom holds that the development of separate species happens quickly, most often when populations become separated by a geographical barrier." this is called speciation. "even if these groups meet again and manage to mate before diverging too far from one another, their offspring will be unfit and die out." this is described as hybrid ) sympatric; viabilityb) allopatric; fertilityc) sympatric; breakdownd) allopatric; breakdown

How many chromosomes does each human cell contain? a. 23 chromosomes b. 26 chromosomes c. 43 chromosomes d. 46 chromosomes

9. the history of life on earth is recorded in

What best explains whether bromine (br) or neon (ne) is more likely to form a covalent bond? bromine forms covalent bonds because it has seven valence electrons, but neon has eight valence electrons and already fulfills the octet rule. bromine forms covalent bonds because it has many electron shells, but neon has only two electron shells and is tightly bound to its electrons. neon forms covalent bonds because it can share its valence electrons, but bromine has seven valence electrons and can gain only one more electron. neon forms covalent bonds because it has only two electron shells, but bromine has many electron shells and will lose electrons in order to fulfill the octet rule.