Former U.S. Vice presidential candidate and Alaska Governor Sarah Palin (R) greets some of the thousands of motorcycle enthusiasts and military veterans participating in 'Rolling Thunder' rally May 29, 2011 in Arlington, Virginia. Although not an official guest, former U.S. Vice presidential candidate and Alaska governor Sarah Palin is expected to participate in today's motorcycle parade from the Pentagon to the National Mall.

A construction worker sweeps up as the final touches are completed on “Comedy Carpet” by British artist Gordon Young, the latest art installation on Blackpool's promenade on October 7, 2011 in Blackpool, England. (Photo by Christopher Furlong/Getty Images)

Yuccas catch fire as the Powerhouse fire makes a fast run toward Lake Hughes, south of Lake Hughes, California, on June 1, 2013. The 19,500-acre wildfire destroyed numerous homes overnight. (Photo by David McNew/Getty Images)

“Tardigrades (commonly known as waterbears or moss piglets) are small, water-dwelling, segmented animals with eight legs. Tardigrades were first discovered in 1773 by Johann August Ephraim Goeze, who called them kleiner Wasserbär, meaning “little water bear” in German. The name Tardigrada means “slow walker” and was given by Lazzaro Spallanzani in 1777. The name water bear comes from the way they walk, reminiscent of a bear's gait. The biggest adults may reach a body length of 1.5 millimetres (0.059 in), the smallest below 0.1 mm. Freshly hatched tardigrades may be smaller than 0.05 mm”. – Wikipedia. Photo: Tardigrades. (Photo by SPL/East News)

A model poses backstage ahead of the NLP show at Mercedes-Benz Fashion Week Australia 2014 at Carriageworks on April 7, 2014 in Sydney, Australia. (Photo by Brendon Thorne/Getty Images)

An orphaned rhesus monkey and white dove that seemed to have lost its mate forged a special bond at the Neilingding Island-Futian National Nature Reserve in China. The monkey was born on the island but had strayed from its mother. Luckily, it was taken in by work staff in the protection center and became friends with the pigeon that had lingered there after possibly losing its mate. (Photo by CNImaging/Photoshot)