A gene is
1. a change in a DNA sequence
2. the 2-letter code representing the alleles inherited from parents
3. a part of a chromosome that controls a particular trait, like eye color
4. a characteristic that is inherited, like eye color

Answerthe global climate during the paleogene departed from the hot and humid conditions of the late mesozoic era and began a cooling and drying trend which dispite having been periodically disrupted by warm periods such as the paleocene-eocene thermal maximum, persists today;