What is a spandrel in evolution?
An evolutionary spandrel is a physical structure or behavioural characteristic that is a by-product from some other functional adaptation.
Is consciousness a spandrel?
Instead of an adaptation, consciousness might be a spandrel (in the sense of Gould and Lewontin Reference Gould and Lewontin1979)—a by-product of some other trait that has adaptive value although consciousness itself has no adaptive value of its own (or may even be dysfunctional).
What is an example of Exaptation in humans?
As an example of an exaptation, Gould (1991) used the large size of the human brain and its function of enabling humans to produce speech. The large brain size, according to his argument, originally arose as an adaptation for some (unspecified) functions in humans’ ancestral past ( Gould, 1991 ).
Is religion a spandrel?
Religion can be understood as a spandrel in the same way that Stephen Jay Gould claims the surface area between two adjacent arches are spandrels.
What are vestigial traits?
Structures that have no apparent function and appear to be residual parts from a past ancestor are called vestigial structures. Examples of vestigial structures include the human appendix, the pelvic bone of a snake, and the wings of flightless birds.
What are spandrels on a house?
In buildings of more than one story the spandrel is the area between the sill of a window and the head of the window below it. In steel or reinforced concrete structures there will sometimes be a spandrel beam extending horizontally from one column to another and supporting a section of wall.
What is Epiphenomenalism dualism?
Epiphenomenalism is the view that mental events are caused by physical events in the brain, but have no effects upon any physical events. The modern discussion of epiphenomenalism, however, traces back to a 19th century context, in which a dualistic view of mental events was assumed to be correct.
Are exaptations rare?
Exaptations are common in both anatomy and behaviour. Interest in exaptation relates to both the process and products of evolution: the process that creates complex traits and the products (functions, anatomical structures, biochemicals, etc.) that may be imperfectly developed.
Are exaptations selected for?
While exaptations are traits that have been enlisted for new uses, adaptations have been shaped by natural selection for their current function, they wrote.
What is an example of Exaptation?
Exaptation is the process of adaptation of a trait for a purpose other than what the trait was evolved for. For instance, an exaptation could be the use of feathers for mating displays or flight in birds which evolved feathers originally to keep warm. An exaptation is also known as pre-adaptation.
Are Exaptations rare?
What is a biological spandrel?
Gould and Lewontin defined a biological spandrel as a byproduct of evolutionary adaptation. Simply put, they’re like ‘leftovers’ of some other trait that evolved. This means that the spandrel isn’t an adaptation to anything in the environment. Instead, it is a secondary trait that arose from the development of another primary trait.
What is a spandrel in architecture?
Stephen Jay Gould and Richard Lewontin used the architectural term spandrel (the triangular gap at the corner of an arch) to describe a byproduct of evolution. In evolutionary biology, a spandrel is a phenotypic characteristic that is a byproduct of the evolution of some other characteristic, rather than a direct product of adaptive selection.
What is the spandrel theory of evolution?
Spandrel (biology) Stephen Jay Gould and Richard Lewontin brought the term into biology in their influential 1979 paper “The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme”. This defined the biological concept and argued the case for a structuralist view of evolution.
Are spandrels just small unimportant byproducts?
In response to the position that spandrels are just small, unimportant byproducts, Gould and Lewontin argue that “we must not recognize that small means unimportant. Spandrels can be as prominent as primary adaptations”. A main example used by Gould and Lewontin is the human brain.