Biologists have hypothesized that high temperatures characterized the early conditions of life on Earth.Which statement would provide the best support for this hypothesis?
A) Human intestinal microbial biota function best at temperatures near the boiling point of water.
B) Bacteria that normally live on human skin thrive at temperatures around 55°C.
C) Most eukaryotic species flourish at temperatures found in hot springs.
D) Reconstructions of ancestral bacterial genes show that the ancestral sequences functioned best at elevated temperatures.
E) The monophyly of the hyperthermophilic bacteria is well established.

Question

Quizplus · Accepted Answer

The reconstruction of ancestral bacterial genes and the finding that they functioned best at elevated temperatures provides direct evidence that high temperatures may have characterized the early conditions of life on Earth. The other choices either do not provide evidence for high temperatures in early Earth conditions or are not directly related to the hypothesis.

Biologists Have Hypothesized That High Temperatures Characterized the Early Conditions