Does that mean that projected times of death based on decomposition (As seen on the pseudo scientific scenes in CSI) could actually be drifting over time due to less decomposition agents?
Anyone that tells you a time of death beyond about 20 hours is lying. And the estimates below that are usually based on processes that haven't changed (loss of body heat, chemical changes in blood, and bacterial processes in the gut).
Sorry, I still don't understand what the bad consequences of some animals dying are. Aren't all animals we need kept and fed by us? What are these good things some animals are doing for the environment?
The term in the field is "Ecosystem Services" if you want to do some googling. We rely on nature for the air we breathe and the water we drink, we haven't figured out how to be independent yet.
Animals, insects, and plants all support each other to become flourishing ecosystems. Larger animals keep the population of smaller animals in check. Smaller animals keep the population of insects in check. I'm not an expert on specifically which animals and insects do what, I just know that a dense, varied ecosystems keep the planet running smoothly.
My favorite writer on the subject right now is 'Charles Eisenstein', who even proposes that ecosystems have a stabilizing effect on the weather -- it might not be that carbon dioxide / higher temperatures produce more chaotic weather systems, but that the ecosystems we are so careless to destroy have regulating effects on the production of clouds and precipitation. The less life there is on earth, the more chaotic the whole system becomes.
You get the point. The food chain can collapse and some animals are doing good things for the environment.