Real Life Zombies in Nature

Ladybugs are harmless and peaceful insects to humans. They are catching to the human eye because of their vibrant colors: red and orange with black spots. These colors signal to birds and other prey that they are however not so peaceful. They have poison in their legs that are released when bitten. This leads to them being relatively protected from their predators. They feed on aphids, which is good for gardeners because aphids harm plants. Plants release chemicals when they are being attacked, and this is what the ladybug searches for to find its prey. It will then use its senses to detect aphids molecules. Once found, the aphid will be torn apart.

Ladybug eating aphids here

Although ladybugs are protected due to their colorful pattern from predators, they are used as a host for a parasitic wasp, Dinocampus Coccinellidae. The infected ladybug turns into a real-life zombie. The female wasp will inject the ladybug with its egg. The ladybug will continue to live its life normally, eating aphids and spreading good luck. The wasp larva then feeds off of the inside of the ladybug. The larva will grow for 3 weeks until it is too big to stay inside the ladybug anymore. It will break through the exoskeleton of the ladybug and form a cocoon on the underside. The ladybug protects the cocoon from predators by covering it with its body.

Ladybug protecting the wasp cocoon here

About seven days later, the adult wasp will leave the cocoon once it is mature enough. This can result in death for the ladybug.

The cycle of the wasp living in the ladybug here

The ladybugs are controlled by the wasp by transferring viruses into the brain of the ladybug. The virus that scientists found in the brains of the controlled ladybugs is called D. Coccinellidae Paralysis Virus, or DcPV. The DcPV is present in the female wasp's tissues surrounding her eggs. It is an extended phenotype from the wasp. The DcPV allows for the wasp to have an increased chance of survival. Once the egg hatches in the ladybug, the virus will reproduce. The DcPV is extremely harmful to the ladybugs--it kills brain cells and forms new viruses in the brain cells. It has no effect on the wasp's health, however. The virus is what controls the ladybug to protect the wasp. It will paralyze the ladybug so that it will stay in place but does not fully paralyze it, which allows the ladybug to defend against predators. The ladybug forfeits signals from its eyes and antennas as time goes on. Its only purpose is to protect. Some ladybugs will die due to the immune response that will try to kill the virus but kills itself too. Some ladybugs will recover. The adult wasp will then have more DcPV and give it to its offspring who will transmit it to their ladybug. This occurs not just in ladybugs, but in species all around the world. 

The protozoan, Plasmodium, that causes malaria inside the mosquito here

Other insects provide parasites a home to feed off of and protect entirely. An example of another organism that controls its host is the protozoan, Plasmodium, in mosquitos that carry malaria. When the protozoan is developing it makes the mosquito only feast on a few humans a night so it has a higher chance of not being squashed. Once it develops, the mosquito suddenly bites many humans per night and can bite multiple times even if full. The mosquito risks its life for the protozoan to find its way into a human host. The protozoan causes the odor of the affected humans to be more appealing to other mosquitos in order to spread more. It is in the parasite's genes to manipulate and control another organism. The parasite's genes take over the mosquito's own genes. Once the parasite is inside the host's body, the genes are mutated, giving the parasite the ability to control the host. In order to make sure that the parasite will have control for a long time, it will change the gene expression of its host by producing compounds on the genes. This increases their survival rate and sometimes causes the host to die.

It is fascinating how a parasite or virus is able to control the actions of a larger organism. The wasp and ladybug were giving the virus a home and a way to survive without even knowing it. Every time a wasp lays its eggs inside a ladybug, it is not only making it so the wasps will have a higher chance of surviving but also the virus. It is incredible how it evolved to be able to control an insect. I read an article a few years ago about parasites that can completely overthrow an insect's instincts and abilities and since then I have not looked at ladybugs the same.