It's Christmas at ground zero / And if the radiation level's OK / I'll go out with you / To see all the new / Mutations on New Year's Day

So the question is: have plants and animals retained over this huge amount of time—whole radiations of mammals have come and gone in this period—have they retained these potentially costly characteristics?

The second [canid group] is the radiation of dogs in South America that began when the first canids arrived about 3 Ma, after crossing the Panama land bridge (Fig. 5.4).

Radiation

Meaning

Noun

Origin

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