Generate an overlapping word between the given two sentences. When you find the overlapping words, they don't have to match exactly, e.g., "survival" and "survive" are valid overlapping words. Little words like "the" or "of" don't count! You must generate significant words which are not the stop words.
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Question: Sentence1: Populations Populations are subsets of a species. 
Sentence2: Gene flow occurs when individuals move into or out of a subset of a species.

Answer: species


Question: Sentence1: information in an organism 's chromosomes cause genetic traits to be passed down to that organism 's offspring. 
Sentence2: information in Man's chromosomes cause genetic traits to be passed down to offspring.

Answer: chromosomes


Question: Sentence1: Deep canyons and valleys are carved out. 
Sentence2: deep valleys are formed by flowing rivers through erosion over long periods of time.

Answer:
Deep