{{about, Interpolation Theory in biology, other types of interpolation, interpolation (disambiguation) The Interpolation Theory, also known as the Intercalation Theory or the Antithetic Theory, is a theory that attempts to explain the origin of the alternation of generations in

plants Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...

. The Interpolation Theory suggests that the sporophyte generation progenated from a haploid, green

algal Algae ( , ; : alga ) are any of a large and diverse group of photosynthetic, eukaryotic organisms. The name is an informal term for a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from un ...

thallus Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or " twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms ...

in which repeated

mitotic In cell biology, mitosis () is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. Cell division by mitosis gives rise to genetically identical cells in which the total number of chromosomes is mainta ...

cell divisions of a

zygote A zygote (, ) is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information of a new individual organism. In multicell ...

produced an

embryo An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm ...

retained on the

and gave rise to the

diploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respecti ...

phase ( sporophyte). Ensuing

evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

caused the sporophyte to become increasingly complex, both organographically and anatomically. The Interpolation Theory was introduced by Čelakovský (1874) as the Antithetic Theory. Bower (1889) further developed this theory and renamed it the Interpolation Theory. The theory was later supported by Overton (1893), Scott (1896), Strasburger (1897), Williams (1904), and others. The gradual

of an independent, sporophyte phase was viewed by Bower as being closely related to the transition from aquatic to terrestrial plant life on

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surf ...

. Evidence supporting this theory can be found in the life cycle of modern

Bryophytes The Bryophyta s.l. are a proposed taxonomic division containing three groups of non-vascular land plants (embryophytes): the liverworts, hornworts and mosses. Bryophyta s.s. consists of the mosses only. They are characteristically limited i ...

in which the sporophyte is physiologically dependent on the

gametophyte A gametophyte () is one of the two alternation of generations, alternating multicellular organism, multicellular phases in the life cycles of plants and algae. It is a haploid multicellular organism that develops from a haploid spore that has on ...

. Competing theories include the Transformation theory, which was introduced as the

Homologous theory Homology may refer to: Sciences Biology * Homology (biology), any characteristic of biological organisms that is derived from a common ancestor *Sequence homology, biological homology between DNA, RNA, or protein sequences * Homologous chro ...

by Čelakovský, and also renamed by Bower.

References

* Gifford, Ernest M. and Adriance S. Foster. ''Morphology and Evolution of Vascular Plants, Third Edition''. New York: W.H. Freeman and Company, 1988. 15–19. * Sinha, A.K. and Anil Kumar. ''Botany for Degree Students – Pteridophyta''. S. Chand. 9–10. * Taylor, Thomas N., Hans Kerp, and Hagen Hass. ''Life History Biology of Early Land Plants: Deciphering the Gametophyte Phase''. PNAS. 2005. vol 102. no 16. * Chopra, R.N., P.K. Kumra. ''Biology of Bryophytes''. New Age International Publishers. 125. * ''How Plants Conquered the Land''. Hans' Paleobotany Pages

Biology theories