Similar results have been found in studies involving different strains of rats, mice, and hamsters. The positivity rate among chemicals tested in rats and mice is ~50%. Some philodendrons are, however, known to be toxic to mice and rats. This occurs in species such as California mice, oldfield mice, Malagasy giant rats and beavers. The genetic material was found working in transgenic mice. Induced parthenogenesis in mice and monkeys often results in abnormal development. The effect is seen in unicellular organisms, green plants, isopods, insects, birds, mice, and hamsters. This includes such animals as domesticated cats, dogs, mice, and gerbils. Humans are much more sensitive to LPS than other animals (e.g., mice). Plants can suffer from damage caused by mice, deer and squirrels. LD is usually determined by tests on animals such as laboratory mice. Prevention requires isolating those who are infected and decreasing contact with the mice. The seeds are eaten by chipmunks, mice, and squirrels. Chlordiazepoxide in laboratory mice studies impairs latent learning. Field mice and lizards are also found.