A physical environment with different species that interact with one another and with non-living thing is called an ecosystem
When the organism become bipedal, they walk with 2 legs so there are 2 arms that were unused. Some of them try to use that hand by grabbing stick or stone, leading to tools. They start to think more to develop tools and their brain capacity become increased.
The ability to use stone tools will help in food digestion since it can break the food easier. This reduces the needs for bigger teeth/jaw.
When a spider weaves a web, this is an innate, or instinctual action. A spider needs no training from other spiders (including its parents) to know how to spin a web.
The sun as producers benefit from that
