Now we move onto invasive animals. Invasive animals may be divided into 2 categories: invertebrates and vertebrates. Invasive insects have many harms to the world around them. Some, like the Asian longhorned beetle (Anoplophora glabripennis), attack North American hardwood trees. Others can cause more serious problems, like attacking cash crops. The soybean cyst nematode (Heterodera glycines) is only 0.08 cm long, but causes $500 million in crop damage yearly, and can reduce soybean yields by over 75%. The most dangerous can be vectors for diseases. The Asian citrus psyllid (Diaphorina citri) attacks citrus crops like lemon and orange trees by carrying the citrus greening disease, also known as HLB (short for huanglongbing, the Chinese name of the disease). However, the most well known vector of all time might be the the Asian tiger mosquito. To most of us, it is simply a pest. However, in places around the world, the Asian tiger mosquito is a deadly killer, transmitting diseases like yellow fever, dengue fever, Chikungunya fever, Usutu virus, and the recently infamous Zika virus, accounting for almost 90,000 human deaths per year. In addition, Asian tiger mosquito also carries a parasite that causes heartworm in canine and feline pets. As demonstrated, invertebrate invasive species are devastatingly harmful.
Vertebrate invasive species carry their own variety of harmful traits. Some, such as house sparrows (Passer domesticus), displace native rare songbirds like eastern bluebirds (Sialia sialis). Others, like the nutria (Myocastor coypus), destroy marshland habitats, which are important for many fish and aquatic bird species. The red lionfish (Pterois volitans) has venomous spines on its back; many an innocent diver has stepped on one and experienced extreme pain or even death. Asian carp (Ctenopharyngodon idella) has received much public attention over the last few years, and that attention is well deserved. Asian carp displaces native fish species and causes them to disappear. In summary, invasive animals can pose just as much of a threat as invasive plants.
Vertebrate invasive species carry their own variety of harmful traits. Some, such as house sparrows (Passer domesticus), displace native rare songbirds like eastern bluebirds (Sialia sialis). Others, like the nutria (Myocastor coypus), destroy marshland habitats, which are important for many fish and aquatic bird species. The red lionfish (Pterois volitans) has venomous spines on its back; many an innocent diver has stepped on one and experienced extreme pain or even death. Asian carp (Ctenopharyngodon idella) has received much public attention over the last few years, and that attention is well deserved. Asian carp displaces native fish species and causes them to disappear. In summary, invasive animals can pose just as much of a threat as invasive plants.
Before we discuss microbes as invasive species, I would like to discuss the methods by which animal invasive species are introduced. As animals are able to move on their own, you would expect the introduction of animals to be much less human-based. However, we must remember that in many cases we are speaking of continent-to continent spreading, which almost always require human intervention. Indeed, it is so, that most invasive species are the cause of human activity. For example, the European starling was first introduced to New York by a man named Eugene Schieffelin in an attempt to introduce all of the birds mentioned in Shakespeare’s works to America. He viewed this as a noble act, though it ended up causing a lot of trouble later on. Rabbits (Oryctolagus cuniculus) were introduced to Australia as a food source, and are now breeding at alarming rates. The nutria was introduced as both a way to control invasive weeds and for fur trade; although it successfully performed the former, it destroyed everything, not only the invasive plants it was intended to.
Essential Question
"Could a genetically engineered invasive species potentially be used in warfare?"