简介：Without warning, millions of mysterious alien "doors" suddenly appear around the globe. In a rush to determine the reason for their arrival, mankind must work together to understand the purpose of these cosmic anomalies. Bizarre incidenc
简介：Have you ever wondered why the human body looks the way it does? Why our hands have five fingers instead of six? Why we walk on two legs instead of four?It took more than 350 million years for the human body to take shape. How did it become the complicat