From Encyclopedia Jr, free information reference for Kids
Vertebrates have a segmented vertebral column and
brain.
Segmentation in biology refers to the division of some metazoan bodies and plant body plans into a series of semi-repetitive segments, and the question of the benefits and costs of doing so. As such, segmentation is related to the more general concept of modularity.
Examples of segmented animals are the annelids and arthropods. Vertebrate vertebrae are also inherited in a segmented way, making it easy for those animals to adapt to have the correct number of these in their vertebral column. This has been extensively studied in mice. Among the plants, the horsetails are a clear example of segmentation.
The process of establishing such a segmented body pattern is discussed in morphogenesis.
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The development of phenotype |
| Key concepts: Genotype-phenotype distinction | Norms of reaction | Gene-environment interaction | Heritability | Quantitative genetics |
| Genetic architecture: Dominance relationship | Epistasis | Polygenic inheritance | Pleiotropy | Plasticity | Canalisation | Fitness landscape |
| Non-genetic influences: Epigenetic inheritance | Epigenetics | Maternal effect | dual inheritance theory |
| Developmental architecture: Segmentation | Modularity |
| Evolution of genetic systems: Evolvability | Mutational robustness | Evolution of sex |
| Influential figures: C. H. Waddington | Richard Lewontin |
| Debates: Nature versus nurture |
| List of evolutionary biology topics |
