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FIRST PLANTS WERE LEAFLESS. "The earliest ancestral vascular plants, dating to the late Silurian 410 Myr ago, were composed of simple or branched axial stems with sporangia but no leaves." 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

FRAGMENT FROM NATURE continues from last weekend and concludes this weekend on the theme of the plant leaf. Few structures have so exemplified life on Earth, nor caused such massive changes as plant leaves, from the vast grasslands to the dense forests. And the more we learn, the more sentient and knowing image of plants have emerged, departing from a stereotype of insensate dumb vegetation. Revisit your smart planetary neighbor with fresh eyes. 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