Salt is notoriously dangerous to land snails; however, some populations of aquatic, freshwater snail have brackish (or a mix of salt and fresh water) water adaptations and live in different parts of a river system. A group of scientists monitored salt concentrations in the habitats of two freshwater snail populations located nearby and recorded the salt level as follows (in ppt, parts per thousand): Population 1 (Day 1): 0.1 ppt (morning), 0.0 ppt (afternoon), 0.1 ppt (evening) Population 2 (Day 1): 0.3 ppt (morning), 0.5 ppt (afternoon), 0.2 ppt (evening) In 3–5 sentences, 1) describe in which population you'd expect to see more adaptations for salt water and 2) explain how such adaptations would become more common in this population.
1) Based on the salt concentrations recorded, population 2 would be expected to have more adaptations for saltwater. This is because the salt concentrations in population 2's habitat are higher compared to population 1, indicating a higher level of saltwater exposure in their environment.
2) These adaptations would become more common in population 2 through natural selection. Individuals with genetic variations that allow them to better tolerate or utilize the brackish water would have a higher survival rate and reproductive success. Over time, these advantageous traits would be passed on to future generations, eventually leading to a population with a higher proportion of individuals with adaptations for saltwater.