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Vibratome Sectioning for Enhanced Preservation of the Cytoarchitecture of the Mammalian Organ of Corti
Published on: June 17, 2011
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Molecular and cellular evolution of corticogenesis in amniotes
Adrián Cárdenas1, Víctor Borrell2
1Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas y Universidad Miguel Hernández, 03550, Sant Joan d'Alacant, Alicante, Spain.
Cellular and Molecular Life Sciences : CMLS
|September 30, 2019
Summary
The evolution of the cerebral cortex in amniotes is linked to changes in neurogenesis and progenitor cells. These developmental shifts explain the expansion and complexity of the cortex, leading to human brain features.
Area of Science:
- Evolutionary biology
- Developmental neuroscience
- Comparative neuroanatomy
Background:
- The cerebral cortex exhibits significant variation in size and complexity across amniotes.
- These differences are attributed to variations in neuron number and composition during embryonic development.
- Understanding these variations sheds light on the evolutionary path to the human neocortex.
Purpose of the Study:
- To review the evolution of neurogenesis and cerebral cortex size in amniotes.
- To discuss developmental mechanisms regulating cortical development across vertebrate and amniote phylogeny.
- To highlight genetic and molecular factors driving the expansion and complexity of the amniote cerebral cortex.
Main Methods:
- Review of existing research on cortical development and evolution.
- Comparative analysis of neurogenesis across vertebrate and amniote species.
- Focus on cellular mechanisms, including basal progenitor cells and indirect neurogenesis.
- Examination of genetic and molecular pathways involved in cortical expansion.
Main Results:
- Variations in neurogenesis during embryonic development drive differences in cortical size and complexity.
- Basal progenitor cells and indirect neurogenesis are crucial for increased neuron number, diversity, and cortical folding in mammals.
- Highly conserved signaling pathways, not just new genes, are key to evolutionary increases in cortical size and complexity.
Conclusions:
- Developmental mechanisms of neurogenesis have profoundly shaped the evolution of the cerebral cortex.
- Cellular innovations like basal progenitors and indirect neurogenesis facilitated mammalian cortical expansion.
- Understanding conserved signaling pathways offers insights into the evolutionary trajectory of amniote and human brain complexity.
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