A drop in testosterone levels around 50,000 years ago led the the development of art and tools, researchers believe. 有研究人员认为,5万年前人体睾丸素水平的降低促进了人类艺术和工具领域的发展。 They say the drop, w...
The cool waters of Wakulla Springs makes it a popular place to beat Florida's heat. Tourists lounge on the May beach, while the locals prefer the opposite bank. Despite the cold-blooded company, people have visited these historic springs for years. B...