1.0 Thinking about the biology of behavior

• Some Renaissance scholars were not content to follow the dictates of the Church; instead, they started to study things directly by observing them—and so it was that modern science was born.
• Descartes advocated a philosophy that, in a sense, gave one part of the universe to science and the other part to the Church.
• He argued that the universe is composed of two elements: (1) physical matter, which behaves according to the laws of nature and is thus a suitable object of scientific investigation—the human body, including the brain, was assumed to be entirely physical, and so were nonhuman animals;

  the human mind (soul, self, or spirit), which lacks physical substance, controls human behavior, obeys no natural laws, and is thus the appropriate purview of the Church.
• Cartesian dualism. as Descartes’s philosophy became known, was sanctioned by the Roman Church, and so the idea that the human brain and the mind are separate entities became even more widely accepted
• Matter: The physical stuff that walks, talks, and plays the accordion.

  
  

  Mind: The nonphysical substance (sometimes equated with the soul)
• Descartes believed in a mechanistic view of the material world — that matter goes about its business and follows its own laws, except when it is interfered with by the mind
• Man's mind, then, simply "pulls the levers" of the body to do its bidding. Exactly how the nonphysical mind interacts with the physical body is a point of contention.
• Descartes believed that the pineal gland in the brain was the locus of interaction between the mind and body because he believed that this gland was the only part of the brain that wasn't a duplicate.
• The pineal gland was described as the “Seat of the Soul” by Renee Descartes and it is located in the center of the brain. The main function of the pineal gland is to receive information about the state of the light-dark cycle from the environment and convey this information by the production and secretion of the hormone melatonin.
• Your pineal gland’s main job is to help control the circadian cycle of sleep and wakefulness by secreting melatonin.
• Man's mind is whole and indivisible, whereas his body can be changed.
• A man is the only dualistic creature. He placed animals in the realm of the purely physical, mechanistic world, acting purely on instinct and on the laws of nature.
• Ethology (the study of animal behavior in the wild) was becoming the dominant approach to the study of behavior in Europe.
• Because instinctive behaviors are not learned, the early ethologists assumed they are entirely inherited. They were wrong, but then so were the early experimental psychologists
• 1.The first line is composed of the many demonstrations that even the most complex psychological changes (e.g., changes in self-awareness, memory, or emotion) can be produced by damage to, or stimulation of, parts of the brain.

  2.The second line of evidence is composed of demonstrations that some nonhuman species, particularly primate species, possess some abilities that were once assumed to be purely psychological and thus purely human.
• Darwin described his theory of evolution—the single most influential theory in the biological sciences.
• Darwin argued that evolution occurs through natural selection. Fitness, in the Darwinian sense, is the ability of an organism to survive and contribute its genes to the next generation.
• SOCIAL DOMINANCE

  The males of many species establish a stable hierarchy of social dominance through combative encounters with other males.
• One obvious problem in relating brain size to intelligence is the fact that larger animals tend to have larger brains, presumably because larger bodies require more brain tissue to control and regulate them.
• In general, the brain stem regulates reflex activities that are critical for survival (e.g., heart rate, respiration, and blood glucose level), whereas the cerebrum is involved in more complex adaptive processes such as learning, perception, and motivation
• Human behavior is subject to genetic variations. The ways in which individuals differ in their intellectual abilities, personalities, and mental health are, to a large extent, functions of their inherited genetic predispositions.
• Genes are composed of a substance called deoxyribonucleic acid, or DNA. DNA contains the biological instructions that allow for the development, growth, and reproduction of life.
• Basic units of heredity that maintain their structural identity from one generation. Strands of genes form chromosomes. Gregor Mendel.
• Diploid is a term referring to an organism with cells that contain two complete sets of chromosomes. Humans are diploids. Most of the body’s cells contain 23 chromosome pairs.
• Homozygous for a gene means that a person has an identical pair of genes on the two chromosomes. Heterozygous for a gene means that a person has an unmatched pair of genes on the two chromosomes.
• •Y chromosome:  genes for 27 proteins

  •X chromosome: genes for approximately 1500 proteins
• Recombination refers to a new combination of genes in the off-spring that yield characteristics not found in either parent.
• Mutation refers to a change in a single gene that is rare, random and often independent of the needs of the organism.
• Artificial selection - organisms with desired traits are chosen to be parents of the next generation