Overview

Project Highlights:

  • Fieldwork on the Isle of Wight and in the Portuguese Beira Litoral Region
  • Training in plant palaeobiology and evolution
  • Investigate the earliest flowering plants

Angiosperms (flowering plants) are an extremely diverse group of terrestrial plants and are composed of an estimated 260,000 species. Angiosperms are characterised by striking morphological diversity, and the group contains an array of life forms that includes herbs, epiphytes, bulbs, aquatic plants, shrubs and trees. The fossil record of pollen grains provides an exceptional window into the early evolution of this plant group, and shows that angiosperms radiated during the Cretaceous period (~150–65 million years ago) (Lupia 1999). This period of diversification marked the onset of a profound change in the composition of the Earth's biota, from earlier Mesozoic vegetation dominated by ferns, conifers and cycads, to modern vegetation dominated by flowering plants.

The fossil record of angiosperm pollen has been used to show that the first flowering plants appeared on Earth during the Early Cretaceous, and that taxonomic and morphological diversity were decoupled during their evolution (Lupia 1999). Additionally, this fossil group has demonstrated that there was a close link between angiosperm evolution and climatic and oceanographic perturbations during the Early Cretaceous (Heimhofer et al. 2006).

This project will use the rich Cretaceous angiosperm fossil pollen record of the UK and Portugal to describe and explain the patterns of speciation among Earth's earliest flowering plants. This will involve releasing fossil angiosperm pollen grains from two rock successions and making morphometric measurements of key features in order to document patterns of morphological change through time.

This will allow an assessment of the degree to which species are separated, and the prevalence of intergrading morphs that blur the boundaries between species. This will provide a record of lineage splitting through time, and will provide data to test whether early angiosperms followed a path of gradual speciation, or whether their evolution was characterised by a punctuated pattern with periods of rapid speciation followed by long-term stasis (Benton and Pearson 2001). 

Wild flowers in the Antelope Valley, California (photo from Flickr).

Methodology

The rocks of the Atherfield Clay (Aptian, Atherfield, Isle of Wight) and the Upper Luz Marls (Aptian, Luz, southern Portugal) will be graphically logged. 150 rock samples will be taken from each of these successions. These samples will be macerated in the laboratory using standard palynological processing techniques (HCl to remove carbonate minerals and HF to remove silicate minerals) in order to release fossil pollen grains. The morphology of angiosperm pollen grains will be quantified by making morphometric measurements of key features. These include the number and size of any apertures present, the nature and thickness of the pollen wall, the overall size of the specimen, and the nature of any surface ornamentation. These morphometric measurements will be plotted against time to examine the patterns of angiosperm evolution as recorded by the morphology

Training and Skills

This project will provide specific training in:

  1. Palynological techniques to extract spores from rock samples and living plants.
  2. The description of plant morphology using morphometric techniques.
  3. The use of transmitted light microscopy and electron microscopy to image micromorphological features of plants.

CENTA students are required to complete 45 days training throughout their PhD including a 10 day placement. In the first year, students will be trained as a single cohort on environmental science, research methods and core skills. Throughout the PhD, training will progress from core skills sets to master classes specific to CENTA research themes.

Timeline

Year 1: Undertake fieldwork to collect rock samples from the Atherfield Formation on the Isle of Wight. Undertake fieldwork to collect rock samples from the Upper Luz Marls at Luz, southern Portugal. Begin processing rock samples to release fossil pollen grains in the laboratory.  

Year 2: Undertake morphometric measurements of angiosperm pollen from the Atherfield Formation and Upper Luz Marls. Prepare a conference presentation to The Micropalaeontological Society Annual General Meeting outlining results from the Atherfield Clay Formation.

Year 3: Prepare a manuscript comparing the results from the Atherfield Formation and Upper Luz Marls. Prepare a presentation for the Botanical Society of America Conference. Write up PhD thesis.

Further Details

Students should have a strong background in Earth science or biology and enthusiasm for plants. Experience of undertaking independent fieldwork and research work in a laboratory is desirable. A driving license would be beneficial for fieldwork. The student will join a well-established team researching ecology, evolution and palaeoenvironmental change at The Open University.

Please contact Luke.Mander@open.ac.uk for further information.

Applications should include:

Apologies that some bits of information are requested multiple times on different forms. Please fill in everything requested.

Applications should be sent to

STEM-EEES-PhD-Student-Recruitment@open.ac.uk  

by 5 pm on 25th January 2017