Domestic Travel

	%Comp	Index
Took air trip within the US past 12 months	74.4%	121
Average trips taken	5.1
Regions visited
South Atlantic	47.5%
Middle Atlantic	42.3%
New England	31.8%
Pacific	38.1%
Mountain	31.3%
East North Central	22.6%
West South Central	16.4%
West North Central	11.4%
East South Central	10.9%
Alaska	2.5%	150
Hawaii	5.7%	113
Travel expenditures past 12 months
Total travel expenditures
Spent $10,000+	29.0%	262
Average expenditure	$9,700	219
Personal Travel and Vacations within the US
Average expenditure	$4,100	193
Average # night spent in hotel/motel past 12 months	16.1

Source: 2008 Ipsos Mendelsohn Natural History Subscriber Study. Indexes based on 2008 Mendelsohn Affluent Survey

Caves are among the predators’ favorite spots.

The brain doesn't much care whether an experience is real.

Humans will never win a sprint against your average quadruped. But our species is well-adapted for the marathon.

Hear author Xiaoming Wang interviewed by Vittorio Maestro, Editor in Chief of Natural History. (MP3, 17 minutes)