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Processing Embryo, Eggshell, and Fungal Culture for Scanning Electron Microscopy
Published on: August 16, 2019
Evolution of avian eggshell structure.
1School of Natural Sciences, Linnaeus University, Kalmar, Sweden.
Journal of Morphology
|October 12, 2011
Summary
Bird eggshells show varying structures, specifically mammillary densities, linked to calcium needs during development. This adaptation reflects differences in growth rates and developmental modes between bird species.
Area of Science:
- Avian biology
- Paleontology
- Evolutionary biology
Background:
- Bird eggshells possess distinct structural features, including mammillary densities.
- These structures are hypothesized to relate to calcium requirements during embryonic development.
Purpose of the Study:
- To investigate the relationship between eggshell structure (mammillary density) and the calcium requirements of birds.
- To determine if eggshell structure reflects different growth rates and developmental modes in avian species.
Main Methods:
- Analysis of eggshell structures, focusing on mammillary densities (number of mammillae per unit of inner eggshell surface area).
- Comparison of mammillary densities between precocial (slow-growing) and altricial (rapidly-growing) bird species.
Main Results:
- Data suggest birds evolve different eggshell structures to manage varying calcium needs.
- Precocial birds exhibit high mammillary density, correlating with slow growth.
- Altricial birds display low mammillary density, associated with rapid growth.
Conclusions:
- Bird eggshell mammillary density is an adaptation to growth rate and developmental mode.
- Eggshell structure, specifically the mammillary layer, serves as an indicator of a bird's breeding biology.
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