What are fossils? what do they tell us about the process of evolution?

What is a fossil?

Fossils are fossilised (petrified) remains of animals/plants. A fossil though, is only a fossil, when it is from a different geological era.

How does that relate to evolution?

Evolution and fossils are very related. When we scan the DNA of different fossils, we find that the DNA can be similar to living species we have today, which helps us trace back their origins.

Tracing back a species origins is not something we do just to see how that species changed along time. When we manage to make an evolutionary chart of a species, we know how they changed, what they changed, and maybe not more, but very importantly, when the previous species were extinguished. If we know when they were extinguished, we can find out what caused that extinction:

- A lack of adaptation.

- Lack of resources.

- Temperature changes.

- Increase of predators.

- Deadly migrations.

- Other natural disasters.

So, in other words, by studying one species, we can study our own planet.

Hope it helped,

BioTeacher101

sheep is a herbivore animal whereas grasshopper belongs to the class chordates but both of them feed on greens.  

if grasshopper and sheep feeding on a pasture land, i do not think both of them will have any impact on each other. however, the number of the species can make difference. since sheep feed on greens, there is a possibility there left no pasture land for the grasshoppers or they may get extinct.