What is urbanization?
Urbanization is generally a city growing and spreading, however in this context it is a city spreading into rural areas, or habitats of species of animals and plants. When this happens it puts animals in dangerous positions, in worlds they aren't used to.
How does it affect us?
You may love to see wildlife near your home, but it can be dangerous for both you and the animals. Animals do not belong in neighborhoods or cities, and they will still act like animals. Animals can eat crops and gardens, and while they aren't the only source of food, if animals reproduce in an urban area they could eat many local plants. Animals will move around the area that was once their habitat, even if a road has fragmented it (see "Fragmentation" page). It could be dangerous for a number of drivers on the road.
How does it affect the animals?
Once an animal is forced to leave its habitat and live in cities and suburbs, it affects them as much, if not more, than it does us. More animals appear on the road, in backyards, and in other dangerous positions, as stated previously. It can ruin the ecosystem as niches are replaced and animals die.