Building large manufacturing facilities can affect ecosystems by increasing the 1
atmospheric quality
2
biodiversity in the area
3
demand for resources such as fossil fuels
4
availability of space and resources for organisms

The answer is Hominids evolved to walk upright on their hind limbs, reducing the need for opposable toes.

As hominids evolved, their brain size and height increased. They left climbing and arboreal lifestyles and begun to walk upright. For that reason their hind limbs became longer and stronger than their front limbs over time. The largest toe on the hind limbs was no longer needed for climbing activities so it became smaller and closer to the other toes.