 Parasites have a really bad rap. People are afraid of them. No one wants to have them. Understandably so because they cause so many diseases and cause so much harm. But if you look closely, they are absolutely fascinating. Evolutionary, fine-tuned, formerly worn cars. They have this one particular purpose. Finding a host, infecting them, and then of course getting to the next host. And you can't beat evolution. You can't beat nature. My name is Alex Meyer and I'm a professor here at the Research School of Biology at Australian National University. Humans, they can be infected by many species. It ranges from very microscopic parasites that live inside of a single cell. Up to the biggest human parasite is a tapeworm. It can be up to 10 meters long. There are diseases that are fairly benign. But then of course there are really severe diseases like malaria where within a matter of days people get from feeling completely fine to being on their death bed. Our lab is focused on the basic biology of malaria parasites. We try to understand how the parasite actually causes disease and what the parasite actually needs in order to survive in the human body. Most people are aware that the blood of an infected person has to be taken up by the mosquito. If an infected with a blood cell with a normal parasite is taken up, nothing happens. It has to be forms that have already been differentiated into male and female. And the male and the female have to find themselves in the stomach of the mosquito in order to fuse and produce a new offspring. It's a very complicated life cycle so we see that as a vulnerability worthwhile to exploit. If we can interfere with this we don't have any transmission anymore and that's part of our research. Parasitology is extremely rewarding. We have made so much progress over the last decades and so many diseases that used to be death sentences for many are still a problem but not anywhere near how severe they were in the past. And even if the contribution is incremental, if you then look back it's quite fascinating how far you can come and what you can discover and also what impact you can have.