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  2. Scientific theory - Wikipedia

    en.wikipedia.org/wiki/Scientific_theory

    A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world. The theory of biological evolution is more than "just a theory".

  3. Scientific law - Wikipedia

    en.wikipedia.org/wiki/Scientific_law

    Scientific law. Scientific laws or laws of science are statements, based on repeated experiments or observations, that describe or predict a range of natural phenomena. [1] The term law has diverse usage in many cases (approximate, accurate, broad, or narrow) across all fields of natural science (physics, chemistry, astronomy, geoscience, biology).

  4. Evolution as fact and theory - Wikipedia

    en.wikipedia.org/wiki/Evolution_as_fact_and_theory

    Professor of biology Jerry Coyne sums up biological evolution succinctly: [3]. Life on Earth evolved gradually beginning with one primitive species – perhaps a self-replicating molecule – that lived more than 3.5 billion years ago; it then branched out over time, throwing off many new and diverse species; and the mechanism for most (but not all) of evolutionary change is natural selection.

  5. Falsifiability - Wikipedia

    en.wikipedia.org/wiki/Falsifiability

    Falsifiability (or refutability) is a deductive standard of evaluation of scientific theories and hypotheses, introduced by the philosopher of science Karl Popper in his book The Logic of Scientific Discovery (1934). [B] A theory or hypothesis is falsifiable if it can be logically contradicted by an empirical test.

  6. Recapitulation theory - Wikipedia

    en.wikipedia.org/wiki/Recapitulation_theory

    The theory of recapitulation, also called the biogenetic law or embryological parallelism—often expressed using Ernst Haeckel's phrase "ontogeny recapitulates phylogeny"—is a historical hypothesis that the development of the embryo of an animal, from fertilization to gestation or hatching (), goes through stages resembling or representing successive adult stages in the evolution of the ...

  7. Biological rules - Wikipedia

    en.wikipedia.org/wiki/Biological_rules

    Biological rules. The pygmy mammoth is an example of insular dwarfism, a case of Foster's rule, its unusually small body size an adaptation to the limited resources of its island home. A biological rule or biological law is a generalized law, principle, or rule of thumb formulated to describe patterns observed in living organisms.

  8. Cell theory - Wikipedia

    en.wikipedia.org/wiki/Cell_theory

    In biology, cell theory is a scientific theory first formulated in the mid-nineteenth century, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells. Cells are the basic unit of structure in all living organisms and also the basic unit ...

  9. Deductive-nomological model - Wikipedia

    en.wikipedia.org/wiki/Deductive-nomological_model

    The deductive-nomological model (DN model) of scientific explanation, also known as Hempel's model, the Hempel–Oppenheim model, the Popper–Hempel model, or the covering law model, is a formal view of scientifically answering questions asking, "Why...?". The DN model poses scientific explanation as a deductive structure, one where truth of ...