Is it possible that a fungus could infect humans and over-run the world, like the cordyceps in the current hit TV series The Last of Us? Anjani Ganase discusses some fantastic parasites and where they are found.
We live in a weird and wonderful world of survival by any means necessary. Some organisms form symbiotic bonds, working together for survival. Some relationships are parasitic where one is robbed of its resources by another. Parasites occur across all the kingdoms. Here are a few parasites that have creatively mastered the art of survival.
Non- photosynthetic (parasitic) plants
Sounds like an oxymoron, but did you know that there about 3,000 species of parasitic plants in the world, making up about one per cent of the flowering plants clade. They are common to tropical forests around the world. Plants hold up the global food chain by directly harnessing sunlight and converting it into food in the process known as photosynthesis. However, the mechanisms of evolution have led to exceptions that evade the rule. Biodiverse forest ecosystems are brutal places for survival where every surface is filled and every ray of sunlight is captured. Under very dimly light canopies, this group of plants evolved to avoid competing for light by tapping into ready-made food sources. They extract directly from the vascular systems of other plants using a special structure called a haustorium which allows them to bore into the tissues of the host plants undetected. Many non-photosynthetic plants are obligate parasites, so there is no need to store chlorophyll in the tissues, and many are not green but are a variety of other colours including red, yellow and white. Other parasitic plants may carry out some photosynthesis but still rely on parasitism to extract nutrients. Some examples of parasitic plants include the dwarf mistletoe, and the corpse flower (Rafflesiaceae family) found in the tropical forests of Indonesia. The corpse flower is the world’s largest flower – about one metre in diameter and weighing up to 11 kilogrammes. The flower releases an odour like rotting flesh to attract flies for pollination while stealing food from the tetrastigma vine.
The marine louse that identifies as a tongue
[caption id="attachment_1000072" align="alignnone" width="768"] A tongue eating louse infecting a Clark's anemonefish. Photo courtesy Christian Gloor -[/caption]
The tongue-eating louse (Cymothoa exigua) is a parasitic isopod that makes its way into the mouth of fish, and unceremoniously removes the fish’s tongue by cutting a major artery to constrict blood flow. When the tongue falls off, the louse then latches on the stub of the tongue filling the space of the tongue to feed off the saliva of the fish. Male Cymothoas may enter the mouth through the gill slits and once attached can undergo a sex change and become female, thereby growing to a large size – up to three centimetres. These isopods are widespread in the warmer waters of the Atlantic Ocean and Gulf of California.
Zombie ant fungus
The Last of Us HBO seri
