Essay On The Cambrian Explosion

Introduction

A whole lot of hypotheses have been used to explain the quick expansion of animal species in the early Cambrian period about from about 541.0 million to about 485.4 million years ago. The most modern explanations for the Cambrian explosion takes pieces of a lot of these hypotheses and melds them together; incorporating genetic, ecologic, abiotic conditions that set the evolutionary wheel in motion. The current state of understanding the Cambrian explosion still remains a topic of open and exciting debate. The processes in the hypotheses can be stand-alone or very tightly interconnected and mutually supporting of another. One can say the complexity of modern Animalia can be attributed to the complexity of the processes that happened during the rapid diversification attributed from an interaction of biotic and abiotic processes in the Cambrian period.

Evolution Debunked?

The Cambrian explosion refers to the speedy diversification of new forms of animals arising within the fossil record in the span of about 20 million years. This may not seem to be the shortest time frame, but in an evolutionary sense it was lightning fast. Some of the early fossils are unusually intact and very well preserved. Two of the more famous locations of Cambrian fossil discoveries are the Burgess Shale discovered by Charles Walcott on August 30, 1909 in Canada and the Maotianshan Shales in Chengijang, china.

The Cambrian explosion is challenging for biologists to interpret because it poses a problem that it seems to be inconsistent with the understood gradual pace of evolutionary change. Even though there is this major difference from this occurrence compared to the ‘normal’ evolutionary model, it doesn’t mean it cannot happen. There has been o...

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... that ensued would have been descendants of a small number of individuals, giving rise to the founder effect. Furthermore, the relatedness between any two individuals would have been very high. Using Hamilton’s rule, the equation: R>C/B can be explained as altruism is increased when relatedness (R) exceeds the ratio of the cost (C) to the individual to the benefit (B) of the recipient of altruism.

Evolutionary pressures due to high relatedness in relation to a population flourishing after a glaciation event could have been enough to overcome the reproductive cost of forming more complex and diverse animals. There are other hypotheses, even some that contradict the idea stated above, stating that early snowball Earths did not so much affect the evolution of life on Earth as resulted from it; this brings up the old argument, “what came first, the chicken or the egg?“.