A key contribution to Darwin's thinking was the concept of limits put on the geometric growth of populations by nature, originally proposed by:

Karl Popper.

Explanation:

. A key contribution to Darwin's thinking was the concept of limits put on the geometric growth of populations by nature, originally proposed

Karl Popper

layer 3 is younger than layer 6.

the principle of segregation describes how pairs of gene variants are separated into reproductive cells. from his data, mendel formulated the principle of segregation. we now know that the segregation of genes occurs during meiosis in eukaryotes, which is a process that produces reproductive cells called gametes.