The first trees evolved around 370 mya along a lakeshore at the foot of the caledonian range. how did these trees have a positive impact on plants and animals?

These first trees had a huge importance for the other plants and for the animals, and this was because:

- they managed to change the structure of the atmosphere by consuming, using, and storing carbon dioxide, and releasing oxygen, which made the atmosphere much more suitable for life.

- they managed to influence the climate, by making it more moist, and also making the ground bellow them cooler.

- they were producing large amounts of biomass, which made the soil types much richer in nutrients, which in turn enabled more and more plants to grow.

- they were a food source of the animals.

the answer is b: 1.4 km/hr