In addition to natural factors, human activity can also alter ecosystems. Conduct research on a human activity that currently affects or can theoretically affect your chosen ecosystem. Use your food web model to explain how this change can affect the competition for food resources. please help

In 1994, telomerase activity was discovered in human cancer cell lines. although telomerase activity is rarely present in human somatic tissue, this discovery indicated that humans do contain the genes for telomerase proteins and telomerase rna. since inappropriate activation of telomerase may contribute to cancer, why do you think the genes coding for this enzyme have been maintained in the human genome throughout evolution?