How does the axial tilt affect life on earth?
The axial tilt is responsible for weather patterns and seasonal changes
Because the Earth is on an axis, some parts of the Earth are farther away from the Sun than others, and we don't get equal sunlight everywhere. The farther a place is from the equator, the more affected it is by the axis tilt, and therefore the more extreme the seasons are.
When places like the Northern hemisphere are away from the sun, it is fall/winter, and the southern hemisphere is in summer/spring, and this is true vice versa. Places like the poles are most affected by the axial tilt, which is why they have the coldest winters.
This tilt then obviously affects where life can exist on Earth and how much. For example, only a few species can really survive in Antarctica and they have to evolve to become that way.