claim: Serotonin induces neuromodulation.
evidence: Whitehorse -LRB- -LSB- wit.ɔʁs -RSB- ; total area population 27,889 as of 2013 -RRB- is the capital , largest , and only city of Yukon and the largest city in northern Canada .. Yukon. Yukon. northern Canada. northern Canada. It was incorporated in 1950 and is located at kilometre 1426 on the Alaska Highway in southern Yukon .. Yukon. Yukon. Alaska Highway. Alaska Highway. Whitehorse 's downtown and Riverdale areas occupy both shores of the Yukon River , which originates in British Columbia and meets the Bering Sea in Alaska .. Yukon. Yukon. Yukon River. Yukon River. British Columbia. British Columbia. Bering Sea. Bering Sea. The city was named after the White Horse Rapids for their resemblance to the mane of a white horse , near Miles Canyon , before the river was dammed .. White Horse Rapids. White Horse Rapids. Miles Canyon. Miles Canyon Basalts. Because of the city 's location in the Whitehorse valley , the climate is milder than comparable northern communities such as Yellowknife .. Yellowknife. Yellowknife. At this latitude winter days are short and summer days have up to about 19 hours of daylight .. Whitehorse , as reported by Guinness World Records , is the city with the least air pollution in the world .. Guinness World Records. Guinness World Records