Problem: Darwin's barnacle studies convinced him that variation arose constantly and not just in response to changed circumstances. In 1854, he completed the last part of his Beagle-related writing and began working full-time on evolution. His thinking changed from the view that species formed in isolated populations only, as on islands, to an emphasis on speciation without isolation; that is, he saw increasing specialisation within large stable populations as continuously exploiting new ecological niches. He conducted empirical research focusing on difficulties with his theory. He studied the developmental and anatomical differences between different breeds of many domestic animals, became actively involved in fancy pigeon breeding, and experimented (with the help of his son Francis) on ways that plant seeds and animals might disperse across oceans to colonise distant islands. By 1856, his theory was much more sophisticated, with a mass of supporting evidence.
By which year had Darwin's theory become more complex and supported by a lot of evidence?
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Answer: 1856


Problem: The official published membership statistics, such as those mentioned above, include only those who submit reports for their personal ministry; official statistics do not include inactive and disfellowshipped individuals or others who might attend their meetings. As a result, only about half of those who self-identified as Jehovah's Witnesses in independent demographic studies are considered active by the faith itself. The 2008 US Pew Forum on Religion & Public Life survey found a low retention rate among members of the religion: about 37% of people raised in the religion continued to identify themselves as Jehovah's Witnesses.
Only about half all Jehovah's Witnesses are actually considered what in the faith itself?
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Answer: active


Problem: In practice, because of sovereignty, any state can withdraw from any treaty at any time. The question of whether this is permitted is really a question of how other states will react to the withdrawal; for instance, another state might impose sanctions or go to war over a treaty violation.
What really determines whether withdrawal from a treaty is permitted?
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Answer:
how other states will react