| Save for contrived laboratory studies with bacteria and fruit flies, it cannot be witnessed. |
| Competition is certainly one environmental circumstance rarely provided in laboratory experiments. |
| Once the virus samples arrived from Hong Kong the experiment and laboratory analysis took only two weeks. |
| We believe that the results of analysis of body fluids and laboratory experiments are obvious. |
| In general, laboratory studies seem to be able to predict extremely well the behaviour of lichens in their natural habitat. |
| Much has been learned about sleep from laboratory studies of non-human animals. |
