chapter4 The Flood
1、The first human footprint on a sandy Australian beach was immediately washed away by the waves. Yet when the invaders advanced inland, they left behind a different footprint, one that they never be expunged.
expunge; expunge sth (from sth ),to remove or get rid of sth,消除
syn, erase，eliminate, defeat, dispose of , eradicate, exclude , get rid of , knock out, phase out , stamp out, wipe out
很多事情你以为想清楚了，结果一说才发现有问题；当你说明白了，一写才知道有漏洞。想是跳跃的思维火花，说是即兴的逻辑片段，写才是沉淀的思想体系。
2、It's common today to explain anything and everything as the result of climate change, but the truth is that earth's climate never rests. It is in constant flux. Every event in history occurred against the background of some climate change.
疑惑_所以我们一直以来被教育的气候变暖或者气候异常是人为原因的结果，是不完全对的吗~
但是，在之后的文章里，作者又表示;some scholars try to exonerate Homo sapiens and blame climate change. But in America, the dung ball around that truth. Even if climate change abetted us, the human contribution was decisive.
3、Without further evidence, there's no way of deciding between the three scenarios. But there are certainly good reason to believe that if Homo sapiens had never gone down under, it would still be home to marsupial lions, disprototons and giant kangaroos.
①这是marsupial; A distinctive characteristic common to these species is that most of the young are carried in a pouch. Well-known marsupials include kangaroos, wallabies, koalas, possums, opossums, wombats, Tasmanian devils, and the recently extinct thylacines.
present-day distribution of marsupials
②Diprotodon, meaning "two forward teeth", is the largest known marsupial ever to have lived. Along with many other members of a group of unusual species
③giant kangaroo
artist's conception
设想一下，澳大利亚大陆上如果都是生活着这样的大型动物没有被人类打扰，那将是什么样的局面，personally thinking, 最后也终究是会被人类占领的.作者认为，the combination of climate change and human hunting is particularly devastating for large animals, since it attacks them from different angles. it is hard to find a good survival strategy that will work simultaneously against multiple threats.
无论从哪个角度或者生活方面，遗传下来的人性总与远古时期人类的发展脱不开联系，人是骨子里喜欢hunting吧，比如现在的各方各面的竞争。
3、As their thermal clothing and hunting techniques improved, Sapiens dared to venture deeper and deeper into the frozen regions. And as they moved north, their clothes, hunting strategies and other survival skills continued to improve.
人类就是这样不段地适应环境发展自己，把自身放在更严峻的环境里当然自身也能更好地发展，这与我们当下的发展有着异曲同工之妙啊，只有把自身放在一个更严峻的环境里，这个环境可以是经历可以是挑战可以是各种远离当下舒适区的状态情况甚至是恶劣的情境，也只有这样，才有发展有成长。
4、在这章的最后，作者是这样结尾; The elephant birds and the giant lemurs, along with most of the other large animals of Madagascar, suddenly vanished about 1500 years ago-- precisely when the first humans set foot on the island.
