The evolutionary consequences of oxygenic photosynthesis: a body size perspective

Abstract

The high concentration of molecular oxygen in Earth's atmosphere is arguably the most conspicuous and geologically important signature of life. Earth's early atmosphere lacked oxygen; accumulation began after the evolution of oxygenic photosynthesis in cyanobacteria around 3.0-2.5 billion years ago (Gya). Concentrations of oxygen have since varied, first reaching near-modern values ~600 million years ago (Mya). These fluctuations have been hypothesized to constrain many biological patterns, among them the evolution of body size. Here, we review the state of knowledge relating oxygen availability to body size. Laboratory studies increasingly illuminate the mechanisms by which organisms can adapt physiologically to the variation in oxygen availability, but the extent to which these findings can be extrapolated to evolutionary timescales remains poorly understood. Experiments confirm that animal size is limited by experimental hypoxia, but show that plant vegetative growth is enhanced due to

Why might they be giants? Towards an understanding of polar gigantism

“…Chapelle and Peck, 2004). Moreover, there is a substantial subset of literature suggesting that atmospheric O 2 and organismal body size have been linked through history (for a review, see Payne et al, 2011). However, even among the gammarid amphipods, which are poster children for polar gigantism, many polar representatives are tiny, and only a small fraction of taxa reach very large sizes even in regions of the highest oxygen availability (Chapelle, 2001;Chapelle and Peck, 2004).…”

The biological and geological contingencies for the rise of oxygen on Earth

“…Indeed, the Cambrian ''explosion'' was probably enabled by the evolution of eukaryotic algae. The rise of oxygen and its effects on animal size and complexity is discussed by Payne et al (2010).…”

Oxygenic photosynthesis and the distribution of chloroplasts

“…1, Payne et al 2010;Frei et al 2009) at the time when the proposed cyanobacterial-to-chloroplast uptake occurred in the early Proterozoic Eon. A potential eukaryotic host could have come from the base of the animal ancestral lineage, possibly related to opisthokonts (Yoon et al 2004).…”

“…The co-editors of this volume (Gantt and Falkowski) have invited specialists from a broad range of disciplines to benefit those readers interested in a comprehensive understanding of oxygenic photosynthesis. Major topics being addressed in the accompanying series of articles relate to the evidence and time-lines of oxygenic photosynthesis on the earth (Farquhar et al 2010), the resultant gains of an aerobic atmosphere and the increase in organismal size and diversity, as well as multicellularity (Payne et al 2010). At the organismal level, some of the biggest questions are: what were the original key characteristics from which the photosynthetic reaction centers were derived (Allen and Williams 2010), what essential changes were required for electron production by the water splitting complex (Williamson et al 2010), and what is the evidence for the timeline of how long cyanobacteria have been around (Schopf 2010)?…”

“…Yet considerable allowances have to be made for a lag in time, differences in local environments before the notable O 2 rise resulted in a transition from anoxia to the estimated ca. 0.001-1.0% O 2 concentration of present (PAL) (Payne et al 2010).…”