Wallace Line by the Sahul Shelf to New Guinea. The biogeographic boundary known as Lydekker's Line, which separates the eastern edge of Wallacea from the Australian region, has a similar origin to the Wallace line. During ice age glacial advances, when the , both Asia and Australia were united with what are now islands on their respective continental shelves as continuous land masses, but the deep water between those two large continental shelf areas was, for over 50 million years, a barrier that kept the flora and fauna of Australia separated from those of Asia. Wallacea consists of islands that were not
Brett Wallace minor-league contract including an invitation to major-league spring training with the San Diego Padres. On June 19, 2015, the Padres called Wallace up. He finished the season with a .302/.374/.521 slash line in 107 plate appearances for the Padres. The following off season, the Padres and Wallace avoided arbitration by agreeing to a $1 million contract for 2016. Wallace was given the starting third base job when Yangervis Solarte was placed on the disabled list with a hamstring injury. Wallace failed to repeat his 2015 production in 2016, finishing the season with a .189/.309/.318 slash line in 256 plate appearances.