Question Statement :

Contrary to popular belief, the idea of evolution didn’t originate with Darwin, but was around for decades before he came along. His accomplishment was to come up with a workable scheme by which it likely occurred. Darwin, it must be said, had unusual exposure to the enormous diversity of life on earth for a man living in his time, through his voyage on the Beagle. However, his eureka moment came not through studying biology, but by reading the paper of an economist, Thomas Malthus, which showed that populations grow faster than the resources to sustain them. It was then that Darwin realized that only those best adapted to their environment would survive and pass on their traits to offspring.

What is the main idea of this paragraph?

It is impossible to come up with big insights without crossing domains.
The idea of evolution did not originate with Darwin.
It is Malthus, not Darwin, who should be given credit for the theory of evolution.
It was the connections that Darwin uncovered more than the facts themselves that made his work important.