Evolution of sexual reproduction and phylogeny of the ancient and enigmatic red algae

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The red algae (Rhodophyta) are an ancient lineage with some members being reported in the fossil record as far back as 1.2 billion years. This group is of considerable economic importance since they contain compounds (agar, carrageenan, etc.) that are used extensively as thickeners in products such as yogurt, ice cream and toothpaste. Genera such as Porphyra (aka. Nori, laverbread) and Palmaria (aka. Dulse) are important food sources and are global billion dollar aquaculture industries. In addition, the red algae are a critical group in the evolution of photosynthetic life on earth through secondary endosymbiosis of chloroplasts. This simply means that several lineages currently capable of photosynthesis have gained that ability by engulfing and keeping other photosynthetic organisms inside them. For example, red algae are the common ancestors to the chloroplasts contained in the division, Heterokontophyta (e.g. large kelps common to Atlantic and Pacific coasts). This was a pivotal event in the evolution of photosynthetic life. Despite the obvious importance of this group, very little is known about what are considered "Bangiophyte" species. Even more fascinating is that even though the fossil, Bangiomorpha, exhibits the first example of sexual reproduction in the fossil record (1.2 BYA), many of these groups do not appear to undergo sexual reproduction or have lost the ability entirely. This proposal focuses on examining these unique organisms and uses molecular techniques to discern if sexual reproduction is or is not occurring within populations. In addition, determination of what a species is (still a challenging concept in many respects) in this unique group. This research will provide a foundation for current genome sequencing projects. In fact, despite considerable advancements in molecular and genomic biology, additional research on these interesting groups in terms of evolution, ecology and biology can only enhance the interpretation of future genomes.