When sea levels rise as dramatically as they did in the Cretaceous, coral reefs will be buried under rising waters and the ideal position, for both photosynthesis and oxygenation, is lost, and reefs can die, like burying a tree’s roots. About 125 mya, reefs made by , which thrived on , began to displace reefs made by stony corals. They may have prevailed because they could tolerate hot and saline waters better than stony corals could. About 116 mya, an , probably caused by volcanism, which temporarily halted rudist domination. But rudists flourished until the late Cretaceous, when they went extinct, perhaps due to changing climate, although there is also evidence that the rudists . Carbon dioxide levels steadily fell from the early Cretaceous until today, temperatures fell during the Cretaceous, and hot-climate organisms gradually became extinct during the Cretaceous. Around 93 mya, , perhaps caused by underwater volcanism, which again seems to have largely been confined to marine biomes. It was much more devastating than the previous one, and rudists were hit hard, although it was a more regional event. That event seems to have , and a family of . On land, , some of which seem to have , also went extinct. There had been a decline in sauropod and ornithischian diversity before that 93 mya extinction, but it subsequently rebounded. In the oceans, biomes beyond 60 degrees latitude were barely impacted, while those closer to the equator were devastated, which suggests that oceanic cooling was related. shows rising oxygen and declining carbon dioxide in the late Cretaceous, which reflected a general cooling trend that began in the mid-Cretaceous. Among the numerous hypotheses posited, late Cretaceous climate changes have been invoked for slowly driving dinosaurs to extinction, in the “they went out with a whimper, not a bang” scenario. However, it seems that dinosaurs did go out with a bang. A big one. Ammonoids seem to have been brought to the brink with nearly marine mass extinctions during their tenure on Earth, and it was no different with that late-Cretaceous extinction. Ammonoids recovered once again, and their lived in the late Cretaceous, but the end-Cretaceous extinction marked their final appearance as they went the way of and other iconic animals.
In 1910, humanity’s greatest balance-of-payment disparity was between the UK and India, as India provided 60 million pounds to the UK, which was more than matched by British Commonwealth payments to the USA of about 80 million pounds. No other nation had a notable impact on international monetary exchanges. The single most telling statistic of the British pillage of India is that as the UK became Earth’s richest nation during its colonial heyday as it led the Industrial Revolution, per capita income in India did not increase between 1757 and 1947, and its . All imperial and colonial efforts were simply plunder operations. The , which was colonialism in everything but the name. The USA’s flag does not fly over Iraq today, but everybody knows who calls the shots. Once in a great while, even American soldiers , but they were always marginalized or silenced.
Is the world changing for the better essay - …
From their , monkeys , and between 35 and 29 mya, according to molecular clock studies, some African monkeys , and , a controversial transitional fruit-eating monkey, appeared about 25 mya. most famous find was a skull in 1948. The primary differences between apes and monkeys are that apes are larger, lost their tails (not having as much need for balancing on tree limbs), and they have a stiffer spine and larger brain. Apes began the descent from canopy to ground. Simians will eat fruit if they can, but some developed thicker tooth enamel. That change meant that they no longer subsisted on soft fruit and leaves, but were eating coarser vegetation, which was a consequence of living in a cooler, dryer world. No Miocene apes were as adapted to leaf eating as today’s apes and leaf-eating monkeys. As with , a prominent speculation today is that those monkeys/apes changed their diets and left the trees as they lost the competitive game with other canopy-dwellers. split from the line that became great apes about 22 mya and became masters of tree-living, with their swinging mode of locomotion.