Diseases and aggressiveness usually
Many snakes can be harmful, but they benefit us by eating rodents such as: mice, rats, and etc. that might carry diseases. Spiders can be harmful as well, they benefit us by eating insects like: house flys, mosquitos, and other insects. They keep the bug population at a normal level.
Ratcon is a brand of pest control used to kill birds and rodents. It is harmful to birds of prey who eat rodents that have been poisoned with it.
Uh, they're big rodents... I guess they could hurt you if they wanted to.
If the inscet has a sickness they can pass it to us.
Predators such as tigers and crocodiles can kill you. Non-predators such as cows and horses can crush you to death. Some also carry diseases and spread germs, especially rodents.
Some give us nutrients. Some are harmful.
Rodents carry many diseases and can transmit these diseases to people.
some are harmful but some are not harmful
Rodents
Snakes help us by eating rodents and other pests.
Over 20,000 rodents are used for cosmetic testing a year.
Yes it is harmful to people.