Seaweeds in cold seas: evolution and carbon acquisition.

Much evidence suggests that life originated in hydrothermal habitats, and for much of the time since the origin of cyanobacteria (at least 2.5 Ga ago) and of eukaryotic algae (at least 2.1 Ga ago) the average sea surface and land surface temperatures were higher than they are today.

Mechanistic interpretation of carbon isotope discrimination by marine macroalgae and seagrasses.

The literature, and previously unpublished data from the authors' laboratories, shows that the δC of organic matter in marine macroalgae and seagrasses collected from the natural environment ranges from -3 to -35‰. While some marine macroalgae have δC values ranging over more than 10‰ within the thallus of an individual (some brown macroalgae), in other cases the range within a species collected over a very wide geographical range is only 5‰ (e.g.

Transport and assimilation of inorganic carbon by Lichina pygmaea under emersed and submersed conditions.

Photosynthetic O evolution by the upper littoral lichen, Lichina pygmaea (Lightf.) C.Ag.