Year: 2022

MAJOR EVOLUTIONARY TRANSITIONS: 1. Replicating molecules to populations of molecules in compartments; 2. Unlinked replicators to chromosomes; 3. RNA as GENE and enzyme to DNA and protein (genetic code); 4. Prokaryotes to eukaryotes; 5. Asexual clones to sexual populations; 6. Protists to animals, plants and fungi (cell differentiation); 6. Solitary individuals to colonies (non-reproductive castes); 7. Primate societies to human societies (language). https://lnkd.in/eZ5-m7K View in LinkedIn

COMMON TRANSITION FEATURES. 1. "Entities that were capable of independent replication before the transition can only replicate as parts of the larger unit after it. For example, free living bacteria evolved into organelles." https://lnkd.in/eZ5-m7K View in LinkedIn

EXAMPLES OF #1: "The origin of chromosomes; the origin of eukaryotes with symbiotically derived organelles; the origin of sex; the origin of multicellular organisms...; and the origin of social groups." Loss of independent reproduction. View in LinkedIn

COMMON TRANSITION FEATURES. 2. "The division of labour...increased efficiency can result from task specialization. For example, in ribo-organisms, nuclei can acids played two roles, as genetic materials and as enzymes, whereas today most enzymes are proteins." https://lnkd.in/eZ5-m7K View in LinkedIn

COMMON TRANSITION FEATURES. 3. "There have been many changes in language, information storage and transmission. Examples include the origin of the genetic code, of sexual reproduction, of epigenetic inheritance and of human language." https://lnkd.in/eZ5-m7K View in LinkedIn

Earthworm Society of Great Britain View in LinkedIn

FRAGMENT FROM NATURE deals for two weekends on the evolution of the human foot. If someone presented me with a design for a human foot that looked like the actual human foot, I probably would have thrown them out of my office. Clunky, messy, bolt-on evolution is why the designs from robotics companies look nothing like the human foot: it was not designed from scratch with a single purpose. All about exaptation: the acquisitions of functions for which they were not originally adapted. View in LinkedIn

NOT FIRST PRINCIPLES. We always assume that evolution has developed the most highly adapted design for a particular function -- think Darwin's Finches -- and how adapted they are to their particular foods. However, most of evolution seems to have been a series of workarounds from an outmoded design to a new use, rather than a design from first principles. The evolution of the human foot is a case in point. It derived from a quadrupedal and arboreal ancestor, trying to make it suitable for bipedal locomotion. Or, put differently, turning a square into a triangle. View in LinkedIn

EXAPTATION. "All epoch-making discoveries have in their wake a revision of pre-existing ideas." http://www.jstor.org/stable/43430678?seq=1#page_scan_tab_contents View in LinkedIn

OBLIGATE BIPEDS. "Of all extant primates, humans are the only obligate bipeds. Highly specialized postcranial adaptations, especially in the lower limb, characterize this unique form of locomotion. The foot is particularly specialized in both its anatomy and its function." https://lnkd.in/eicfqZV View in LinkedIn