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WHOPPING INCREASE IN STOMATA DENSITIES. "By the time large laminate leaves became widespread in late Devonian/early Carboniferous fossil floras, the concentration of atmospheric CO2 had fallen, and stomatal densities had increased by up to a 100 times the value of early vascular land plant axes." http://aob.oxfordjournals.org/content/96/3/345.full.pdf View in LinkedIn

BIG LEAF PROBLEM. "In contrast, a megaphyll intercepting at least twice as much solar energy (per unit area of the photosynthetic organ) reached temperatures approaching the highly conserved lethal threshold of extant tropical taxa because the same limited evaporative cooling was inadequate to dissipate the absorbed thermal energy." http://aob.oxfordjournals.org/content/96/3/345.full.pdf View in LinkedIn

AVOIDING LETHAL OVER-HEATING. "The rise in stomatal density held special significance for the evolution of leaves by permitting greater evaporative cooling and alleviating the requirement for convective heat loss. Simulations indicate that archaic land plants with axial stems, few stomata, and low transpiration rates only avoided lethal over-heating because they intercepted a minimal quantity of solar energy." http://aob.oxfordjournals.org/content/96/3/345.full.pdf View in LinkedIn

GLOBAL SUCCESS. "Evidently, leaves are a global success. However, the advent of large megaphylls took place some 40–50 million years (Myr) after the origination of vascular land plants, suggesting that they were far from an evolutionary inevitability." http://aob.oxfordjournals.org/content/96/3/345.full.pdf View in LinkedIn

IMPACT ON INSECTS. "Moreover, plant activities appear to have caused rates of evolution in terrestrial animals to accelerate. Late Palaeozoic insect and tetrapod faunas diversified together with terrestrial plants, and enhanced burial of organic carbon raised global oxygen levels, fuelling a spectacular radiation of insect gigantism." http://aob.oxfordjournals.org/content/96/3/345.full.pdf View in LinkedIn

"STOMATA are microscopic valves on plant surfaces that originated over 400 million years (Myr) ago and facilitated the greening of Earth's continents by permitting efficient shoot–atmosphere gas exchange and plant hydration." https://lnkd.in/ehcV6zt View in LinkedIn

REFLEXIVE CYCLE. "In the long term, plants brought about a gradual and continual alteration of the global environment that modified selection pressures on subsequent generations, effectively facilitating their own evolution through the process of niche construction." http://aob.oxfordjournals.org/content/96/3/345.full.pdf View in LinkedIn

GLOBAL SUCCESS. "Evidently, leaves are a global success. However, the advent of large megaphylls took place some 40–50 million years (Myr) after the origination of vascular land plants, suggesting that they were far from an evolutionary inevitability." http://aob.oxfordjournals.org/content/96/3/345.full.pdf View in LinkedIn

EXAPTATION OF GENES. "Whether megaphylls, which arose independently in four vascular plant lineages (ferns, sphenopsids, progymnosperms and seed plants), recruited the same gene systems is open to investigation. However, this does seem a possibility given that a common developmental mechanism for leaf production appears to have been recruited independently at least twice in the evolution of land plants." http://aob.oxfordjournals.org/content/96/3/345.full.pdf View in LinkedIn

INCREASED RESPIRATORY CHANNELS. "The large fall in CO2 corresponded with a marked rise in the stomatal density of vascular land plants, with densities increasing a 100-fold from 5–10mm (-2) on early vascular plant axes to 800–1000 mm (-2) on the cuticles of late Carboniferous megaphylls." http://aob.oxfordjournals.org/content/96/3/345.full.pdf View in LinkedIn