Honours Projects

Potential projects in the MEEP lab for 2013 and 2014 are described below. We are also happy to discuss any ideas for Honours projects in any of the research areas described on the Molecular Ecology, Evolution, and Phylogenetics site.

Mitochondrion

The role of junk DNA in termite biology

Supervisor: Nathan Lo

Biology has yielded many surprises, but one of the greatest has been the discovery that standard protein-coding genes in animal genomes represent only a small fraction of the genome size, sometimes less than 2%. A large fraction of the genome consists of repetitive elements, which for a long time have been considered “junk DNA”. We have discovered repetitive elements in termites that appear to play an important role in termite biology. This project will involve examining the expression of these repetitive elements, and silencing their expression to look for phenotypic effects.

Heathcliffe

Evolution of the heaviest cockroach on earth

Supervisors: Nathan Lo & Simon Ho

Macropanesthia rhinoceros is an endemic Australian cockroach, and also the world’s heaviest. It ranges from outback northern Queensland all the way to the Great Barrier Reef. It digs burrows in the soil up to a metre deep, and gives birth to live young, both unique traits among cockroaches. Unlike its pest relatives, M. rhinoceros is quite charismatic - it is wingless, slow moving, and has a strict diet of eucalyptus leaves. The aim of this project is to study how and when this species evolved, by sequencing its DNA and performing phylogenetic comparisons with related cockroaches. One hypothesis is that it evolved from wood-dwelling, rainforest cockroach species, and developed its unique traits as a result of increasing aridity in Australia over the last 15 million years. This project will involve learning molecular and computational techniques used in evolutionary biology

Termites

Polygamy in termites

Supervisors: Nathan Lo & Ben Oldroyd

In most termite species, colonies are formed by one queen and king, who then have up to a few million offspring. However, in Nasutitermes exitiosus – a species found in Sydney - colonies often have multiple kings and queens. This is expected to lead to some conflict between the parents for their share in reproduction, and the reasons for its evolution are unknown. One possibility is that under difficult ecological conditions it is easier to form a colony with multiple reproductives rather than just two. This project involves field work and genetic analysis to determine the number of kings and queens in N. exitiosus colonies, and examination of the conditions under which they are found.

Tick

Are Australian ticks spreading Lyme disease?

Supervisor: Nathan Lo

Ticks are obligate bloodsucking arthropods second only to mosquitoes as worldwide vectors of human diseases. A number of Ixodes spp., including the paralysis tick I. holocyclus, have geographic distributions along the east coast of Australia, overlapping with the bulk of the human population. The presence in Australia of Lyme borreliosis - the most common tick-borne disease in the world - is controversial. Lyme is caused by at least three species of the spirochete genus Borrelia. On the basis of studies on ticks during the 1990s, the current advice from the NSW Health Service is that there is “no evidence for the presence of Lyme borreliosis in Australia”. However, there have been many cases of tick-bite victims in Australia who have developed Lyme-like disease symptoms, and number of medical experts believe that the disease is present here. In this project you will use molecular techniques to examine Australian ticks for the presence of Borrelia and other potential pathogens.

Lars the polar bear

Phylogenetic relationships and evolutionary timescale of carnivores

Supervisor: Simon Ho

This project will examine the phylogenetic relationships and evolutionary timescale of mammalian carnivores. The research will involve collecting DNA sequences from online repositories, phylogenetic analysis, and other computational techniques.

Termite

Rates of molecular evolution in insects

Supervisor: Simon Ho

The 'molecular clock' hypothesis states that the rate of molecular evolution is constant among organisms. Although it is now widely known that evolutionary rates show significant variation, the patterns of variation have not been characterised in detail in insects. Some particularly interesting questions include: (i) How much rate variation exists among orders of insects? (ii) Do mitochondrial and nuclear genomes show similar patterns of rates? (iii) To what extent does natural selection affect the patterns of rate variation in coding genes compared with non-coding DNA? This project will involve collecting DNA sequence data from online databases and published studies. Evolutionary rates will be estimated using current phylogenetic methods. This project will provide the opportunity to develop bioinformatic skills and will gain a broad appreciation of statistical and computational techniques in evolutionary biology.