Book Reviewed: Many Things Under a Rock: The Mysteries of Octopuses by David Scheel

The inner lives of octopuses Octopuses are invertebrates that lack skeleton, and their legs have no femur, tibia or fibula, no feet, and no toes to wiggle. Instead, octopuses have a hydrostatic skeleton, combining muscular contraction and water's resistance to compression, to generate movement. The octopus genome illustrates how intelligence evolved in this animal. With its eight prehensile arms lined with suckers, camera-like eyes, elaborate repertoire of camouflage tricks and spooky intelligence, the octopus is like no other creature on Earth, which explains the evolution of their cognitive skills. The octopus’ genome is as large as a human, and they contain a greater number of protein-coding genes than Homo sapiens. One of the most remarkable gene groups is the protocadherin, which regulates the development of neurons and the short-range interactions between them. The octopus has 168 of these genes more than twice as many as mammals. This resonates with the creature’s unusually large brain and the organ’s even-stranger anatomy. Of the octopus's half a billion neurons, two-thirds spill out from its head through its arms, without the involvement of long-range fibers such as those in vertebrate spinal cords. This gives independent computing power to its arms. They have more autonomy than human arms. Each has its own miniature brain, giving it a degree of independence from the animal's central brain. On the contrary, the human’s nervous system is highly centralized, with the brain as the seat of sensory integration and other actions. They are the closest we will come to meeting an intelligent alien. The author narrates his experience as an explorer of octopus in its natural habitats off the coasts of Alaska, Washington State, and Japan. This book does not explain the octopus’ biology or physiology but discusses from a behavior ecologist’s perspective. Octopus is a nature’s wonder, because this soft and boneless aquatic species survives with otherer formidable animals like sharks, killer whales, and eels. How do they hunt while avoiding danger in the ocean? Their anatomical structure, skills, camouflage, and a unique nervous system that matches human consciousness.

Book Reviewed: Beasts Before Us: The Untold Story of Mammal Origins and Evolution by Elsa Panciroli

The extinct mammals Humans and dinosaurs co-exist in the cartoon world of the Flintstones. In a similar fashion, the mammalian ancestors shared their history with the Tyrannosaur Rex and related dinosaurs before the K-Pg mass extinction sixty-six million years ago. Some of these mammalian species included placental mammals that survived the catastrophic extinction. The surviving mammalian species, after the catastrophic event, rapidly diversified which was spurred on by the death of dinosaur predators, and emerging environmental factors that offered new opportunities. Two groups of animals existed in the late carboniferous period, between 320 and 315 million years ago, they were synapsids and sauropsids. The sauropsids are ancestral reptiles and some of these species evolved into birds. and synapsid evolved into mammalian species. The Cretaceous–Paleogene (K–Pg) extinction event is the mass extinction of most plant and animal species on the planet about sixty-six million years ago when the Chicxulub impactor, a plummeting asteroid or comet, seven miles long, hit the planet that brought an abrupt and calamitous end to most species. The evolution of mammals’ centers on the shapes of the teeth, the evolution of the middle ear bones, fur, hair, warm-bloodedness, and proportionally larger brains than reptiles of similar size. Mammals could chew food, and hunt carefully. They had mouse-like earflaps for detecting sound that provided advantage, helping them avoid predators and communicate with one another in new ways for competing and caregiving. These changes increased brain size. Not only did more grey matter help them learn information from the senses, but they could also compute emerging behaviors. Their teeth also helped in digging. The mammalian ability to feed underdeveloped offspring on milk increased the survival of litter. Bipedalism is the basic adaptation of the hominid which is responsible for skeletal changes. The earliest hominin species, and non-bipedal knuckle-walkers (the gorillas, and chimpanzees), evolved from a common ancestor, Sahelanthropus or Orrorin species, about six million years ago. The bipedal hominin species underwent further evolution into the Homo Sapiens who are around 250, 000 years. The author briefly discusses the revolution in methodologies and new techniques in the field of paleobiology that estimated the origins of ancient mammalian species. Fossil records and ancient skeletons are the principal sources for studying the history living species, but now they compute enormous datasets of bone shapes, and estimate the form and function mathematically, similar to the methods used in evaluating the strength of building materials. This technique has helped paleobiologists learn the evolutionary history of mammals. There has been a radical transformation in the science of extinct life. The anatomy of various species is put together and predicted how animals emerged into distinct groups. My only gripe about this book is that discussions in some chapters are not stimulating, and there are no photographs and few illustrations.

Book Reviewed: Parasites: The Inside Story Hardcover by Scott Lyell Gardner, Judy Diamond, and Gabor R. Rácz

Diversity in living systems Parasites are usually described in negative terms, often as blood suckers, freeloaders, scroungers, flunkies, and deadbeats. In this book, the authors describe how parasites evolve by focusing on three kinds of parasites: the nematodes, the flat­ worms or platyhelminths, and the thorny-headed worms. These are endoparasites that live and thrive inside their hosts. The scientific data obtained with regards to parasite-host relationships between trematodes and snails, and tapeworms and whales makes an interesting read. Geohelminths manipulate and suppress their hosts' immune systems enabling them to reduce inflammation and decrease the likelihood that the host can expel them. It is also interesting to learn how species of parasitic helminth evolved independently to its specific lifestyle using a wide choice of hosts. Recently, scientists using an artificially streamlined version of Mycoplasma mycoides, a parasitic bacterium found in the guts of goats, synthetically eliminated 41 percent of its genes leaving all but the most essential sequences, which produced free-living cells without the need for a host tissue. Genetic drifting plays an important role in evolutionary mechanisms. The authors suggest deforestation, loss of native habitats and global warming may destroy the ecosystem that includes parasites-host relationship. But no scientific data is presented to show global warming has a direct impact on this relationship. This is a short book of 224 pages, in many sections, the discussion is insufficient and not stimulating.