1 . Mosquitoes
Its difficult to grasp how such a small creature can be so destructive, but rest assured, the mosquito is by far the most destructive creature on this list. Even though the mosquito is incapable of causing any significant structural damage, it more than makes up for this by infecting over 300 million people a year with Malaria and Dengue, two life threatening diseases. Furthermore, in the United States, mosquitoes are responsible for infecting over 30,000 people with the West Niles Virus since 2001; 1,200 of which have resulted in death. Currently, mosquitoes have gained the spotlight thanks to their contribution in spreading the Zika Virus, which has been linked to thousands of birth defects.
2 . Tsetse Flies
Though not destructive in the structural sense, Tsetse flies are estimated to be responsible for the endangerment of anywhere between 250,000 to 300,000 people annually. Tsetse flies are large biting flies that inhabit large regions of Africa between the Sahara and Kalahari Deserts. They live by feeding on the blood of vertebrate animals and are the primary African biological vectors of trypanosomes, which causes human sleeping sickness and animal trypanosomiasis, also known as nagana.
3 . Lionfish
Beautiful and deadly the lionfish is also highly destructive. Native to the IndoPacific, the lionfish has established itself as a significant invasive species of the East Coast of the United States and has been described as one of the most aggressively invasive species on the planet. It aggressively preys on small fish and invertebrates and are territorial towards other reef fish. This poses a major threat to reef ecological systems which consequently could be experiencing a decrease in Atlantic reef diversity by as much as 80%.
4 . Brazilian Wandering Spider
Brazilian wandering spiders, also called armed spiders or banana spiders, belong to the genus Phoneutria, which means murderess in Greek. And its no wonder why since this spider is one of the most venomous on Earth. Its bite can be deadly to humans, especially children, although antivenom makes death unlikely. For the record, the Guinness Book of World Records has named the Brazilian wandering spider the worlds most venomous multiple times.
5 . Fat
With this critter, its no so much a destructive impact on an large scale but rather a destructive impact on a personal scale. Fat
6 . Beavers
Beavers have the potential to do great good or great damage to their environment. Their dam building habits have been linked to the beneficial creation of new habitats which benefit a variety of animals. On the other hand, this same behavior has led to some flooding and millions of dollars worth of damage annually. This figure includes their destructive impact on timber and agricultural crops.
7 . Rats
A common house pet, rats are one of the most destructive vertebrates. For starters, when introduced into locations where rats previously did not exist they can cause a huge amount of environmental degradation. In fact, the black rat is considered to be one of the worlds most invasive species and has contributed to the extinction of many wildlife species including birds, reptiles, small invertebrates and even mammals. Aside from its invasive nature, rats are also know to carry diseases such as the bubonic plague, Lassa fever, leptospirosis, and Hantavirus infection.
8 . Deer Tick
The loathsome deer tick, now known as the blacklegged tick, is defined more by the disease it spreads than by its own characteristics. These bloodsucking members of the arachnid family were brought to the publics attention in the mid1970s when it was discovered that they are the primary (and possibly only) transmitters of Lyme disease. According to the CDC, Its estimated that about 300,000 people in the United States are diagnosed with Lyme disease each year.
9 . Fleas
Fleas might be considered relatively harmless albeit annoying, but theyre among the deadliest bugs in history. Thats because their disease carrying nature is responsibly for the death of almost twothirds of Europe during the Black Plague. Fleas are considered vectors, meaning they transport bacteria and disease from one host to another (e.g. the bubonic plague from rodents to humans).
10 . Giant African Snails
The giant African land snail is considered to be one of the most damaging snails in the world because they will eat almost any vegetation they can find and have proven to be quite destructive to plaster and stucco structures. Giant African land snails are also known to carry parasites that can lead to meningitis in humans. As if thats not enough, they also reproduce quickly, producing around 1,200 eggs in a single year.