Lifeonlandprobablybeganabout430millionyearsago,thoughti...
问题详情：Lifeonlandprobablybeganabout430millionyearsago,thoughtithadexistedinthewaterforperhapsaslongas3,000millionyears.Whenwethinkofthefirstlifeonland,weprobablythinkofstrangeanimalscomingoutoftheoce...