PROGRESS UPDATE FOR LIFE: AN UNAUTHORISED BIOGRAPHY BY RICHARD FORTEY
In Chapter 5, Fortey discusses the new ecological roles and niches that occurred after the Cambrian explosion (photosynthesizing producers, grazers, hunters, predators, prey, parasites, viruses etc); the development and nature of marine reefs; the appearance of the first sea urchins, starfish, crustaceans, fish and predators such as nautiloids and sea scorpions; the graptolite chronometers of the Ordovician and Silurian periods; and the mystery of the conodont identify is finally solved. This chapter had a particularly amusing diversion when the author describes his pursuit of trilobite fossils all over the world, usually to the least likely tourist destinations, and his trip to Thailand.
Chapter 6, in which the greening of the world is discussed; from algal mats, to the first plants with waxy cuticles (liverworts) and stomata, the perculiar reproduction of ferns, to reproduction via spores. Fortey has an interesting perspective on plants, describing them as "a photosynthetic factory with problems of distribution and supply like any manufacturer". the author also discusses the first freshwater fish, the first land insects and the first land vertebrates. There is an interesting section on tetrapods, the number of toes of ancient tetrapods and whether they evolved from lobe-fined fish or lungfish
Chapter 7 focuses on the Carboniferous coal forests of 330 million years ago. The development of leaves, the engineering marvel of trunks, and the development of seeds all play a role in the proliferation of trees. This chapter also deals with the all important question of which came first - the chicken or the egg. Fortey discusses the different types of eggs (amphibian and reptile) and how large, amniotic eggs protected from desiccation by a tough membrane allowed animals to depend less on on the presence of water for reproduction. It was also in these Carboniferous forests that flying insects evolved.
Chapter 7 does not neglect the Carboniferous oceans which were the heyday of brachiopods and consisted of forest of sea lilies and coral reefs. "The seas thronged with life". Another interesting section in this chapter discusses the continuity of sharks from the Carboniferous period to modern times.
Chapter 8 covers the concept of continental drift, along with the formation and breakup of the supercontinent Pangaea, and the development of something which could be called a food chain. Fortey takes us on a tour around Permian age Pangaea: the glaciers, the desserts, rainforests in the tropics and the shallow seas around the continent. An interesting consequence of the evaporation of the shallow seas is the mineral deposits, which were useful to the Industrial Revolution millions of years after the event. The mass extinctions related to Pangaea are also mentioned. The end Permian mass extinction would result in the loss of approximately 96% of all marine species and 70% of terrestrial vertebrate species, including all the calcite coral reefs and trilobites. "There was never again a time when the world was so available to the wondering tetrapod - at least until the invention of the boat".
Richard Fortey has a knack with words and descriptions that make the reader feel they were there witnessing events.
OTHER BOOKS THAT COVER TOPICS DISCUSSED IN CHAPTER 5-8
-Planet of the Bugs; Evolution and the Rise of Insects by Scott Richard Shaw
-The Emerald Planet: How Plants Changed Earth's History by David Beerling
-Your Inner Fish by Neil Shubin
-The Worst of Times: How Life on Earth Survived Eighty Million Years of Extinctions by Paul B. Wignall
-When Life Nearly Died: The Greatest Mass Extinction of All Time by Michael J. Benton