Emery and Clayton provide examples of corvid behavior in both the lab and the wild to highlight how these birds show evidence of each of their 4 cognitive tools. When they described the behavior of hand-raised laboratory ravens, who managed to pull up strings baited with meat that were suspended below their perches, they used this example to demonstrate in laboratory corvids.

Clara wrote the following hypothesis for an experiment about acidophilic bacteria. bacteria cells will stop dividing in a basic (alkaline) environment because of the high ph. which statement is the best way to restate the hypothesis so that it is more specific? growing acidophilic bacteria in some environments will cause the cells to stop dividing because of ph. if the ph of their environment is changed, acidophilic bacterial cell division will be affected. if the environment of acidophilic bacterial cells becomes alkaline, the bacteria will stop dividing. the more alkaline an environment, the less cell division will occur in bacteria.