9(l) Primary Productivity of Plants - Physical Geography

Flowers produce the energy they need to sustain life by means of photosynthesis

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Land colonization was perhaps the Devonian’s most interesting event. The adaptations invented by aquatic life to survive in terrestrial environments were many and varied. Most importantly, the organism would no longer be surrounded by water and had to manage . Nutrient acquisition and reproductive practices would have to change, and the protection that water provided from was gone; plants and animals devised methods to protect themselves from the Sun’s radiation. Also, moving on land and in the air became major bioengineering projects for animals. Breathing air instead of water presented challenges. The pioneers who left water led both aquatic and terrestrial existences. Amphibians had both , and arthropods, whose exoskeletons readily solved the desiccation and structural support problems, evolved to replace their gills, which were probably book gills.

The bodies of living organisms within a unit area make up a standing crop of biomass

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The rest of this chapter will trace many important preindustrial developments which helped set the stage for the Industrial Revolution, which is humanity’s fourth and most recent Epochal Event. But until the last few centuries in Europe preceding the Industrial Revolution, the basics among all civilizations did not appreciably change. Agriculture provided a local and stable energy supply that allowed for sedentism, forests were removed to make way for crops, and domestic animals were used to provide labor and/or flesh products, while their manure helped replenish soil nutrients depleted by agriculture. Virtually everywhere that agriculture appeared, so did civilization, with varying levels of urbanity. Elites dominated all civilizations, and they almost always invoked either a divine nature or divine sanction to justify their status, and they always engaged in conspicuous economic consumption. Cities situated on low-energy transportation lanes, which were almost always bodies of water, exploited forested and agricultural hinterlands, which were worked by peasants and slaves, while cities housed professionals and the elite. Forests and agriculture provided the primary energy supply of all preindustrial civilizations, which was usually supplemented with the products and services of domestic animals. All preindustrial civilizations were steeply hierarchical - economically, socially, and politically – and the means of production provided small surpluses that supported a small elite and professional class. Fighting over resources and plunder has been the primary predilection of all civilizations for all time, except for a very brief interlude at the beginnings of .

In today’s hunter-gatherer societies, the EROI for killing large animals dwarfs all other food sources. The EROI, of calories produced divided by those burned during the hours of labor invested, for large game (a deer, for example), is more than 100, and on average four times that of small game, fifteen times that of birds, about eight times that of roots and tubers, and 10-15 times that of seeds and nuts. The hunter-gatherer EROI for seeds, nuts, and birds is around ten-to-one. An average-sized adult African elephant carcass provides about 13 million calories, which would sustain a band of 12 people for a year if they could eat it all before it rotted and did not die of protein poisoning. The EROI for those easily killed proboscideans when humans invaded the Western Hemisphere could have been in the hundreds and even more than one thousand. Large animals have always been the mother lode of hunter-gatherer peoples, and the consensus among anthropologists is that no instincts urge a hunter to kill only what is needed, but a hunter will kill whatever he can. That finding partly derives from studying modern hunter-gatherers. There is no doubt that when early humans intruded into environments that never before encountered humans, where animals would have had no intrinsic fear of humans, people would have had an exceptionally easy time killing all large animals encountered. Animals without experience around humans, such as Antarctic penguins, are easily approached and killed. As happened innumerable times in the historical era, intruding humans killed all the naïve animals that they could. The only animals that survived developed a healthy fear of humans and avoided them, but how many could develop that fear before they were all killed? From the very beginning of the , . More than 500 million years later, a new kind of animal appeared that turned that advantage into a fatal disadvantage, as it found a way to mine that energy stored in large animals, and it quickly plundered it to exhaustion whenever it could.

Biodiesel fuel from Hemp Seed Oil

Ornithischians started slowly and began to become common in the late Jurassic, just when the greatest biological innovation in the past 300 million years began: the appearance of , which first bloomed about 160 mya. Until that time, plant survival strategies included how to avoid being eaten by animals, whether it was bark, height, poisonous foliage, etc. Flowering plants adopted a different strategy by laying out a banquet for animals. The primary benefit for plants was , as well as attracting animals that did not seek to eat the plants and even ended up protecting them. The advantage for animals was an easily acquired and tasty meal. It was the greatest direct symbiosis between plants and animals ever, other than plants providing the oxygen that animals breathe, which is inadvertent. The two primary aspirations that seed plants achieve for successful reproduction are becoming fertilized via pollination and placing seeds where they can become viable offspring (and feces fertilizer could only help). Flowering plants, also called angiosperms, did not invent animal assistance from whole cloth. Some Jurassic insects have been found in association with (conifer) cones, and were probably doing the work that the wind previously performed. Like the , attracting animals to plants, to eat the pollen and nectar, was like a reproductive enzyme: animals carried the key to the lock to initiate reproduction. Other animals ate the fruit and thereby spread the seeds. That relationship did not become significant until the mid-Cretaceous. Angiosperms mature faster and produce more seeds than gymnosperms do. By the Cretaceous’s end, angiosperms dominated tropical biomes where ferns and cycads used to thrive, and they pushed conifers to the high latitudes, just as they have today. That tropical dominance is probably related to the insect population, which prefers warm climates. Angiosperms became Earth’s dominant plants after the and comprise more than 90% of plant species today.

Hemp seed oil can be used as is in bio-diesel engines

From the Permian extinction’s devastation arose a reptilian sheep called . Fossil hunters of early Triassic sediments have been frustrated for many years, as nearly are , because it was about the Permian extinction’s only land animal survivor. There has been about why it survived when almost nothing else did. No single animal ever dominated Earth’s land masses as thoroughly as did during the early Triassic. was probably a burrower (many have likened to a pig because of that burrowing), which may have provided the shelter needed to survive the Permian holocaust. It may also have been a and could eat most surviving plants. But some think that its survival, when almost every other species died, was due to luck. Luck is a surprisingly common proposed explanation for evolutionary events and outcomes, and some creatures seemed to be in the right place at the right time while others were in the wrong place at the wrong time. The spread of was also aided by two other facts: the land masses , so could simply walk to dominance of Earth; and few predators capable of eating a survived. One (being semi-aquatic may have also helped species survive the Permian extinction), as did , but not much else did. was a , as were the dominant land animals before the Permian extinction.