The visible portion of the 13-foot-tall (4-meter-tall) Christmas tree isn't ancient, but its root system has been growing for 9,550 years, according to a team led by Leif Kullman, professor at UmeÃ¥ University's department of ecology and environmental science in Sweden. Enlarge Photo.
Here are the facts: 1  More than 100 million animals are reported killed by hunters each year.  The vast majority of species that are hunted -- waterfowl, upland birds, mourning doves, squirrels, raccoons, rabbits, crows, coyotes, etc. -- provide minimal sustenance and do not require population control.
The Best Estimate. Mathematician, computer science expert and animal rights advocate Brian Tomasik has attempted to catalog estimates of the number of individual animals in a variety of groupings. According to his data, the total number of individual animals on the earth adds up to approximately 20,000,121,091,000,000,000. This can be written as 20 quintillion, or 20 billion billion.