How would life on earTh be different if earth's axis were straight up and down rather then tilted and why?

If Earth's axis were straight up and down, there would be no significant seasonal variations in temperature and daylight. This would lead to a more uniform climate across the planet, with equatorial regions remaining hot and polar areas remaining cold year-round. Ecosystems would likely be drastically altered, as species adapted to seasonal changes would struggle to survive. Additionally, agricultural patterns would change, affecting food production and biodiversity.