In evolutionary developmental biology, the concept of genetic assimilation describes a process by which an environmentally induced phenotype becomes fixed as an inherited trait through natural selection. Biologist Conrad Waddington demonstrated this mechanism by subjecting fruit fly embryos to heat shock, which caused them to develop crossveinless wings. By selectively breeding the individuals that exhibited this response over several generations, Waddington produced a line of flies that consistently developed crossveinless wings even in the complete absence of temperature stress. This empirical demonstration showed that phenotypic plasticity can precede and channel subsequent evolutionary changes in the genome.
Desmos Graphing Calculator
Verbal·Craft and Structure·Text Structure and Purpose
mediumWhich choice best states the function of the underlined sentence in the text as a whole?
A
It qualifies an earlier claim by limiting the effects of heat shock to fruit fly embryos.
B
It identifies a methodological limitation of selective breeding experiments.
C
It states the broad evolutionary conclusion that Waddington’s experimental results are offered to support.
D
It describes the molecular mechanism by which heat shock alters wing development.