Humans share several features with salamanders due to common…
Humans share several features with salamanders due to common ancestry. Certain genes and proteins are nearly identical between the two species; both species have four limbs with a similar skeletal structure; the species’ early embryos are very similar; and where the salamander has a functional tail, humans have a vestigial tailbone. In evolutionary terms, these are examples of
Read DetailsThe chemical composition of the gases surrounding the Earth…
The chemical composition of the gases surrounding the Earth has changed substantially over the past 4 billion years. One notable change was due to the emergence of photosynthetic organisms. The process of photosynthesis increased the amount of what gas in the atmosphere?
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