Thermoreceptors detect body temperature and send impulses to the brain for analysis. if body temperature is low, the brain will signal skeletal muscles to perform brief, repeated contractions to generate heat. in this example, what is the effector?  skeletal muscles  body temperature  thermoreceptors  brain

The effector is the skeletal muscles

they each offer a fresh glut of resources to the organisms that can arrive and exploit them. as individuals and new species continue to appear, they actively and passively alter the environment. competition for shared resources increases, local abiotic and biotic conditions shift, and the relative abundances of species change accordingly. the process is called ecological succession, and it is one of the earliest and most well-known concepts in ecology.

i think that is new experiments yield untrustworthy data and should be carefully considered, because you don't know what will happen with the experiments.