Evolution: Components and Mechanisms
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Evolution: Components and Mechanisms introduces the many recent discoveries and insights that have added to the discipline of organic evolution, and combines them with the key topics needed to gain a fundamental understanding of the mechanisms of evolution. Each chapter covers an important topic or factor pertinent to a modern understanding of evolutionary theory, allowing easy access to particular topics for either study or review. Many chapters are cross-referenced.
Modern evolutionary theory has expanded significantly within only the past two to three decades. In recent times the definition of a gene has evolved, the definition of organic evolution itself is in need of some modification, the number of known mechanisms of evolutionary change has increased dramatically, and the emphasis placed on opportunity and contingency has increased. This book synthesizes these changes and presents many of the novel topics in evolutionary theory in an accessible and thorough format.
This book is an ideal, up-to-date resource for biologists, geneticists, evolutionary biologists, developmental biologists, and researchers in, as well as students and academics in these areas and professional scientists in many subfields of biology.
- Discusses many of the mechanisms responsible for evolutionary change
- Includes an appendix that provides a brief synopsis of these mechanisms with most discussed in greater detail in respective chapters
- Aids readers in their organization and understanding of the material by addressing the basic concepts and topics surrounding organic evolution
- Covers some topics not typically addressed, such as opportunity, contingency, symbiosis, and progress
cells—really amounting in the great majority of cases to a form of mutation or parasitism. In the rare event that the plasmid does confer adaptive benefit (adaptive in the current environment), then of course the few deriving that benefit will quickly outcompete and outgrow the competition—just like the case of the rare beneficial mutation. Remembering that evolution cannot plan for the future or carry harmful mechanisms forward because they “might” benefit future individuals would argue against
below the ear’s attachment to the head. A few people instead have their earlobe fused with the head/neck and lacking the “hanging” lobe. Perhaps attached earlobes are problematic for people who are into earrings, but other than that there is no indication that having one form or the other is in any way beneficial or detrimental to one’s health or genetic fitness. What person would examine and judge a perspective mate in terms of their earlobes? Such neutral variation within a population is
in the genomes of most organisms—especially so in the more complex eukaryotes, and continued mutations in such genes contribute to further neutral evolution of the species. Some Chromosomal Mutations Can Be Neutral Beyond mutations in single genes or in classes of noncoding DNA, chromosomal mutations also occur from time to time. These involve various deletions, translocations, duplications, or inversions of small to sizable segments of chromosomes (Chapter 5). Some of these are clearly
depends greatly on environmental change. This can happen through actual environmental change (which we know has occurred extensively over much of the Earth over geologic time), or it can occur through the displacement of organisms into new environments—as when seeds, insects, or birds arrive on isolated oceanic islands or disjunct continents. Without environmental change, natural selection would eventually “perfect” (as much as possible given the available genetic variation) each species to be
the power of evolution, with documentation of evolutionary transitions that Darwin could have only dreamed about. Donald R. Prothero That the sequence of fossils in the Earth’s strata documents evolution is now accepted by scientists as an irrefutable truth. Ernst Mayr Some workers have said that we now have enough solid evidence that evolution has occurred even without the abundant visible evidence found in the fossil record. Still, it is convenient that the fossil record exists and