Welcome to the Website of the 
Aquatic Division of the molzoolab@UJ


The Molecular Zoology Lab is a molecular research laboratory based at the Department of Zoology, University of Johannesburg, South Africa. 

The Aquatic Division uses genetic and genomic tools to study marine and freshwater animals in southern Africa and elsewhere. Our main focus areas are biogeography, phylogeography, phylogenetics, population genetics, genomics/transcriptomics, conservation biology and invasion biology.

Contact: 
Prof. Peter Teske, University of Johannesburg, Auckland Park 2006, Johannesburg, South Africa; Email: pteske101@gmail.com



                                                                                             Photo: Robert Harcourt


Student Projects/Positions:

We invite applications for the following research projects/positions. Interested South African or international students should please contact the laboratory at pteske101@gmail.com. 



Masters or PhD position

Genetic investigation of female philopatry in the raggedtooth shark, Carcharias taurus 

Start date: immediately
 
The Molecular Zoology Laboratory at the University of Johannesburg (Auckland Park, South Africa) invites applications for a full-time PhD or MSc position (with the option to upgrade to PhD) to investigate sex-biased genetic population structure in the raggedtooth shark (Carcharias taurus) along the South African coast.  

The position is funded by the National Research Foundation (NRF) for a maximum of 2 years and is available immediately. Although the NRF gives preference to local applicants, students from outside of South Africa are encouraged to apply and will be selected if they are clearly more qualified, particularly if one or more of the following criteria apply: a) a distinction in their previous degree (e.g. BSc honours); b) good genetic laboratory skills, and preferably experience working with microsatellites; c) at least one publication in a reputable journal.

This project is part of a multidisciplinary collaboration including Prof. Peter Teske (University of Johannesburg), Dr Kolobe Mmonwa and Dr Matt Dicken (both KwaZulu-Natal Sharks Board). The student will be based at the University of Johannesburg (http://bit.ly/1mnAZHo) for the duration of the project, with occasional visits to the KwaZulu-Natal Shark Board (www.shark.co.za). There will be no sampling trips, as all genetic samples have already been collected.

Remuneration is R (ZAR) 40 000 per year for an MSc position and R 60 000 for a PhD position + top-up funding from the University of Johannesburg. A short summary of the project is included below. 

Interested students should please contact Prof. Peter Teske: pteske101@gmail.com. Please include a) a full CV; b) contact information of 3 academic referees, and c) a personal statement describing research experience, interests and career goals (500 words maximum).

Summary:
The raggedtooth shark (Carcharias taurus) is listed by the IUCN as globally vulnerable. Off South Africa, it is commonly found along the East and South coasts, from Cape Town to northern KwaZulu-Natal. Tag-recapture studies suggest that this species exhibits philopatry to specific pupping, mating and gestating areas. This project aims to use genetic samples from mature female and juvenile sharks to investigate the extent of site fidelity, and test for genetic differentiation among sharks from different nursery areas.



PhD position

Marine hybridisation on a changing planet

Start date: immediately

The Molecular Zoology Laboratory (molzoolab) at the University of Johannesburg (Auckland Park, South Africa) invites applications for a full-time PhD position in genomic and transcriptomic work on marine invertebrates. The position is funded by the National Research Foundation for a maximum of 3 years and is available immediately. Remuneration is R (ZAR) 60 000 per year + top-up funding from the University of Johannesburg. 

Research topic: Hybridisation, or the production of viable offspring as a result of crosses between divergent genetic lineages, is an increasingly frequent phenomenon. Opportunities for hybridisation are greatly enhanced by habitat alteration (e.g. removing physical barriers) and anthropogenic transport globally. Human-­induced climate change forces species to migrate away from their native habitats, which may lead to hybridisation among previously isolated species. Opportunities for hybridisation thus exist at an unprecedented level, which directly disrupts evolutionary trajectories. This has important conservation implications, as hybridisation directly increases extinction rates of rare / endangered species and causes major alterations in species distributions. 

Research project: The successful candidate will combine population genetic analyses with multigenerational experimental studies to understand the consequences of recent hybridisation events. Fitness measures under controlled environmental conditions are a valuable tool to study how anthropogenically induced climate change and hybridisation will alter the future distribution of the world’s biota. Whole transcriptome (i.e. all the genes that are being expressed) analyses will be used to understand future changes resulting from the hybridisation of marine organisms. The candidate will join a dynamic research group (molzoolab, University of Johannesburg) and work closely with scientists at the University of Southampton and Rhodes University.

Supervisors:
Prof. Peter Teske (Zoology Department, University of Johannesburg)
Dr. Marc Rius (Ocean & Earth Science, National Oceanography Centre Southampton, University of Southampton)
Prof. Christopher McQuaid (Department of Zoology and Entomology, Rhodes University)



Zoology Honours projects

Start date: Reserve yours as soon as possible! To apply, send an email to pteske101@gmail.com, and provide some background on your previous marks, skills and interests.


1. Genetic connectivity in the world's largest copepod

Collaborator: Ryan Wasserman, South African Institute of Aquatic Biodiversity, Grahamstown

Temporary water bodies (ephemeral ponds) are home to a number of crustaceans with interesting life cycles. Since these environments dry out completely for periods of time, population persistence for many species is reliant on the production of dormant eggs capable of withstanding desiccation.

Since temporary water bodies are scattered across the landscape and are essentially isolated, how are crustaceans dispersed between these water bodies? Research has shown that dormant eggs are transported across the landscape via mammal, bird and wind dispersal. These mechanisms of egg transport therefore facilitate genetic connectivity between habitats. 

This Honours project will be directed at addressing issues of connectivity among spatially separated populations of the copepod species Lovenula raynerae. This recently described copepod species is thought to be the largest freshwater copepod known to science and is known only from the Eastern Cape of South Africa. The project will specifically be assessing genetic connectivity in relation to distance between isolated water bodies. 

All samples have already been collected and genetic laboratory protocols have been optimised, so this is a low-risk project that will likely result in at least one scientific publication. There is also a good chance that a student can extend the project at MSc level.

No background in genetics is required, but students who have some laboratory skills (e.g. a degree in biochemistry, microbiology or similar) will be preferred.


2. Biological explorations of drowned paleo-estuaries in south-eastern Africa

Collaborator: Fiona Mackay, Oceanographic Research Institute, Durban

This project will explore the faunal composition of drowned estuaries on the Thukela Bank, south-eastern Africa. It will explore the hypothesis that estuarine species have persisted in these habitats since the last ice age, when sea levels were much lower, and explore their relationship with modern estuarine populations.

We will use a combination of morphological and genetic methods to establish the relationship between the fauna of the Thukela Bank and that of south-eastern Africa's contemporary estuarine habitats. Two hypotheses will be compared to explain the observed faunal similarities: a) the fauna on the Thukela Bank is an ancient deep-water fauna potentially of coastal origin that has established itself over millions of years; b) the Bank is home to relict estuarine fauna that has rapidly adapted to deep-water conditions when sea levels rose at the end of the last ice age; in both cases, it is possible that it represents a unique fauna that may not be found anywhere else, and that requires specific management strategies.

The research has implications for the sustainable management of the region's offshore fauna, but can also provide information on the adaptation of estuarine species to rising sea levels in the near future. Depending on the results, there is also a good chance that a student can extend the project at MSc level.

No background in genetics is required, but students who have some laboratory skills (e.g. a degree in biochemistry, microbiology or similar) will be preferred.



Postdoctoral Positions/Career Advancement Fellowships

Emerging researchers wishing to get experience and improve their publication profile are invited to join the lab and suggest a research project of their choice, or contribute to ongoing projects. We are particularly interested in researchers who have experience with next-generation sequencing data analyses (or at least with unix-based bioinformatics). For details on deadlines and eligibility, please see https://nrfsubmission.nrf.ac.za.

Postdocs:

South African or foreign researchers holding a PhD can apply for NRF Free-Standing Postdoctoral Fellowships (R150 000 + R10 000 for travel).

Career Advancement Fellowhips:

South Africans with a minimum of two years of postdoctoral experience can apply for funding via the NRF's Career Advancement Fellowship Programme (R350 000 per year + 100 000 for research). 



Internships
Got a gap year and want to get involved in some interesting research? In most cases, our interns get their own projects and are expected to publish at least one paper. 
                             





Latest Publications:

Teske PR, Bader S, Golla TR (in press)
Passive dispersal against an ocean current. Marine Ecology Progress Series.
Teske2014_PyuraInvasion.pdf

Genetic methods have revelead that in marine region dominated by boundary currents, passive dispersal may often take place in the direction opposite to the boundary current. This suggests that wind-driven inshore currents play an important role in dispersing such species. We studied gene flow in a coastal limpet with direct development along the south-east coast of South Africa. Two major regional lineages were identified, and even though dispersal was primarily southward (from the northern lineage into the southern lineage), suggesting that the southward-flowing Agulhas Current is important in facilitating connectivity, there was also evidence for some northward dispersal. A detailed analysis of the single haplotype responsible for this finding suggested that its genetic assignment to the northern lineage was questionable, and a likely artefact of incomplete lineage sorting. A survey of the literature indicates that shared ancestral polymorphisms may have influenced inferences of dispersal against the Agulhas Current, and we suggest that not even significant genetic structure may be sufficient to obtain reliable gene flow estimates in such cases.


Teske PR, Sandoval-Castillo J, van Sebille E, Waters J, Beheregaray LB (2015)
On-shelf larval retention limits population connectivity in a coastal broadcast spawner. Marine Ecology Progress Series 531:1-12 Selected as "Feature Article" for the July 2015 edition
Teske2015_On-shelfLarvalRetention

Boundary currents (such as the East Australian Current, the California Current and the Agulhas Current) are often considered to be the primary drivers of connectivity among populations of coastal species. Using a combination of microsatellite data and oceanographic modelling, we show that boundary currents in temperate southern Australia are not particularly important in maintaining connectivity in the coastal snail Nerita atramentosa, a species whose larvae remain in the plankton for several months. Few of the species' larvae ever reach the region's boundary currents, and those that do will not return to the coast in time to complete development. As a result, the species' genetic structure follows a pattern of "isolation by geographic distance", suggesting that most planktonic larvae settle close to their parent habitat.


Teske PR, Sandoval-Castillo J, Waters J, Beheregaray LB (2014)
Can novel genetic analyses help to identify low-dispersal marine invasive species? Ecology and Evolution 4:2848-2866.
Teske2014_PyuraInvasion.pdf
The genetic study of introduced species is presently dominated by analyses that identify signature of recent colonisation by means of summary statistics. Unfortunately, such approaches cannot be used in low-dispersal species, in which recently established populations originating from elsewhere in the species' native range also experience periods of low population size because they are founded by few individuals. We tested whether coalescent-based molecular analyses that provide detailed information about demographic history support the hypothesis that a sea squirt whose distribution is centered on Tasmaniaq was recently introduced to mainland Australia and New Zealand. Methods comparing trends in population size were no more informative than summary statistics, likely because of recent intra-Tasmanian dispersal. However, estimates of divergence between putatively native and introduced populations provided information at a temporal scale suitable to differentiate between recent introductions and ancient divergence, and confirmed that all three non-Tasmanian populations were founded during the period of European settlement.

Teske PR, Sandoval-Castillo J, Sasaki M, Beheregaray LB (2015)
Invasion success of a habitat-forming marine invertebrate is limited by lower-than-expected dispersal ability. Marine Ecology Progress Series 536:221-227.
Teske2014_PyuraInvasion.pdf
Even though ascidians can readily reach far away locations by attaching themselves to the hulls of ships, what happens in the invaded marine communities depends strongly on habitat availability. We used polymorphic microsatellites to study an invasive population of the ascidian Pyura doppelgangera in Adelaide (South Australia). This species has considerable potential to destroy native communities by overgrowing them. Adelaide's coastline is essentially a sandy beach, and P. doppelgangera is only present on artificial structures. Unlike in northern New Zealand (where rocky shore habitat is continuous), physical removal can potentially eliminate this species before it can spread to other sites in South Australia. This study suggests that solitary ascidians' 1-day larval dispersal phase cannot facilitate long-distance dispersal, and that conclusions to the contrary may be the result of incomplete lineage sorting of more slowly mutating DNA sequence data.

Teske PR, Papadopoulos I, Barker NP, McQuaid CD (2013)
Disperal barriers and stochastic reproductive success do not explain small-scale genetic structure in a broadcast-dispersing mussel. Marine Ecology Progress Series 482: 133-140.
Teske2014_PyuraInvasion.pdf
Females of the marine mussel Perna perna are genetically structured between bays and the open coast, but we found no strong support for two commonly invoked pre-settlement factors that could explain small-scale genetic structure within coastal regions. Genetic heterogeneity could not be explained by nearshore circulation resulting in asymmetrical dispersal, nor did we find evidence for temporal changes in population structure resulting from chance mating success. While we cannot presently explain the mechanism that has driven genetic structure in female P. perna, our study points to a role for species- and gender-specific adaptive constraints in driving genetic structure. 

Teske PR, Zardi GI, McQuaid CD, Nicastro K (2013)
Two sides of the same coin: extinctions and originations across the Atlantic/Indian Ocean boundary as a consequence of the same climate oscillation. Frontiers of Biogeography 5: 48-59.
Teske2014_PyuraInvasion.pdf
We discuss a model of range extension followed by divergence, in which the same climate oscillations that resulted in the extinction of coastal species in south-western Africa also sowed the seeds of new biodiversity.