Answer:
1,000 kcal
Explanation:
As a general rule, every trophic level only gains 10% of the energy from the trophic level.
So, the grass has 100,000 kcal of energy. Assuming the bird eats grass, it only gets 10,000 kcal of energy. Assuming the fox eats the bird, it only gains 1,000 kcal of energy.
...The origin of life on Earth is a set of paradoxes. In order for life to have gotten started, there must have been a genetic molecule.. something like DNA or RNA—capable of passing along blueprints for making proteins, the workhorse molecules of life.
Early hypothesis was not based on experimentation
The first land plants appeared around 470 million years ago, during the Ordovician period, when life was diversifying rapidly. They were non-vascular plants, like mosses and liverworts, that didn't have deep roots