Can you fill the blank with a phrase? If you can use more than one word, I would consider: "Evolution is still going on today" or "Evolution still goes on today." If you are only allowed to fill the blank with a single word, then: "Evolution goes on today." For example, we could write a paragraph like this: Evolution is not just something that occurred in the past. Evolution goes on today. Natural selection continues, and so does evolution. According to a recent BBC news story, Swedish scientists have discovered the first proven example of speciation actually occurring, and the discovery was made in Galapagos finches, the same population Darwin studied. They found a population of hybrid birds on one island. Genetically, these hybrids should have been able to breed with their parent species and been absorbed back into the population, but "Due to an inability to recognise the songs of the new males, native females won't pair with [them]" and thus they are actually a new species.

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