some birds of paradise in New Guinea and manakins in South America actually create their own sun spot on the forest floor by pruning adjacent trees. It was once thought that this ‘gardening’ was to minimise the risk of predation, but as our understanding of avian vision improved, it became clear that the birds were manipulating the background colour to maximise the visual contrast of their plumage and the overall effectiveness of their sexual displays.
哇,自己给自己造舞台
If you have observed captive birds of prey, you will see that they often move their head from side to side or up and down as they watch you approach. They do this because they are alternating your image on their two foveas, the shallow one for close up, the deep one for distance.
咦我只注意过猫头鹰歪脑袋!它们不能转眼珠,所以就转脑袋。
不过恍惚也有印象鸟类的脑袋转得特别快。。观鸟不够多,下次出门带望远镜(还想搞个好的镜头
这本书里说到鸟类的 retina 不像脊椎动物的那样分布有血管,而是单独由一个叫 pecten 的器官提供,这样看东西不用隔着血管会更清晰。
于是我上网想查查看 pecten 长什么样,结果查到维基的图上有画血管,那是不是画错了啊?按照我的理解所有的血管都在 pecten 里?维基说“大大减少 retina 里血管的数量”,而我查到的别的来源都说是 no blood vessels…虽然“减少到零”也勉强能算“大大减少”吧…
ps. Retina 的中文是“视网膜”,但既然鸟类的 retina 里没有血管,那叫“网”就不合适了。
pps. Fovea 的中文是“中央窝”,但鸟类有两个 fovea,那也不能叫中央了吧。
Type 2 includes birds like ducks and the woodcock, whose eyes are high up on the sides of the head. They don’t have a great forward view and most don’t need to see their bill tip because they rely on other senses when feeding, but they do have panoramic vision, above and behind – helping them detect potential predators. Interestingly, the views from each eye barely overlap, so they probably see two separate images.
如果两只眼睛看到的图片没有重叠的话,那不是就很难推测物体的深度吗还是说它们要求不高所以边运动边推测也可以…
我觉得很有意思的是,如果是像人的眼睛那样两只都在前面,那么前行的时候靠一只眼睛推测深度就不精确;但鸭子眼睛在两边,所以前行的时候几乎就是和视线垂直,两边的深度可以较好地计算…(有机器人是这样做的吗?)但前方到底是怎样呢…只能靠别的感官吗…
Amazingly, we train ourselves to ‘reverse’ the inverse image on our retinas. In a famous experiment conducted in 1961, Dr Irwin Moon wore image-inverting spectacles that effectively turned the world upside down. At first he found it horribly disorientating, but after eight days of wearing the spectacles Dr Moon had adjusted and ‘saw’ the world the right way up again. To prove it, he drove his motorbike and took his plane for a spin – without mishap. Moon’s extreme experiment provided irrefutable evidence that we ‘see’ with our brain rather than with our eyes.
哇,我以前有听说过因为眼睛的成像是上下颠倒的,所以婴儿刚出生的时候看到的世界是反的,后来才调整过来的,原来同样的过程也可以在成人身上实现!大脑好神奇!
因为居留卡太漂亮我今天又忍不住向室友炫耀,
我:耶,我有永居卡耶
室友:耶,我失业了耶
我:你知道永居什么意思吗,就是我可以自由选择居住地和职业了,以前我的居留是和居留目的挂钩的
室友:哇,那也就是说以前你不能像我这样失业了还四处晃悠?
我:是哟,我可以合法失业了
室友:太好了,我们一起失业吧:
但是居留卡真的好漂亮嘛
https://www.ergo.de/de/Ratgeber/gesundheit/bildschirmarbeit
Auge wird überanstrengt, weil es sich, beispielsweise beim Abtippen eines Textes, permanent an unterschiedliche Lese-Entfernungen anpassen muss. Es findet ein ständiger Blickwechsel zwischen Tastatur, Papier und Bildschirm statt. Bei manchen Menschen führt das sogar zu Kopfschmerzen.
嘿嘿,盲打大法好
这里面说眼睛和屏幕要保持 50 cm 的距离,感觉电脑可以,手机完全不行…嗯少玩手机吧
——连续玩了四个半小时手机的我说道。
我月初去柏林看舞蹈的时候就觉得要是我搞舞台机械设计也不错喔但我对这个世界的可能性一无所知…从小到大都没有见过什么炫酷的演出,也许见过一两个但是没有产生过什么想法…对职业的想象也很局限