| 50473 |
Creator |
c3baa1aae2495d9fcf383c433b46bfe0 |
| 50473 |
Creator |
ext-26977260ad80d839ea99812ac401d679 |
| 50473 |
Creator |
ext-8cbb7a5aee2819b96dd6baab40dd861a |
| 50473 |
Date |
2018-01 |
| 50473 |
Date |
2017-08-18 |
| 50473 |
Is Part Of |
repository |
| 50473 |
Is Part Of |
p1474919X |
| 50473 |
abstract |
Birds’ eggshells are primarily composed of calcite, an abundant polymorph of calcium
carbonate (CaCO<sub>3</sub>). However, the eggshells of some species are coated with
spherules of vaterite, a rare and thermodynamically unstable polymorph of CaCO<sub>3</sub>,
the function of which remains unknown. Here we experimentally test the mechanical
and physiological effects of the vaterite coating on eggshells of the Greater Ani
<i>Crotophaga major</i>, a tropical cuckoo. Vaterite removal did not affect vapour
conductance rates across the eggshell, indicating that the vaterite coating does not
influence gas exchange during embryonic development. By contrast, nanoindentation
revealed that the hardness and elasticity of vaterite is similar to that of calcite,
and white light interferometry showed that the vaterite layer increased the total
thickness of the shell cuticle by up to 10%. Furthermore, calculations of contact
mechanics found that when two eggs come into contact, the depth of the surface deformation
caused by the contact is far less than the thickness of the vaterite coating. These
results suggest the layer of vaterite spherules may act as a ‘shock absorber’ for
the underlying calcite shell, protecting it from mechanical damage caused by collision
with other eggs in the nest and reducing the risk of eggshell fracture during incubation. |
| 50473 |
authorList |
authors |
| 50473 |
issue |
1 |
| 50473 |
status |
peerReviewed |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/631128 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/631129 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/631130 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/631131 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/631132 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/631133 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/652655 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/652667 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/652668 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/652669 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/652670 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/652671 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/659958 |
| 50473 |
uri |
http://data.open.ac.uk/oro/document/661479 |
| 50473 |
volume |
160 |
| 50473 |
type |
AcademicArticle |
| 50473 |
type |
Article |
| 50473 |
label |
Portugal, Steven J.; Bowen, James and Riehl, Christina (2017). A rare mineral,
vaterite, acts as a shock absorber in the eggshell of a communally nesting bird.
Ibis: international journal of avian science, 160(1) pp. 173–178. |
| 50473 |
label |
Portugal, Steven J.; Bowen, James and Riehl, Christina (2018). A rare mineral,
vaterite, acts as a shock absorber in the eggshell of a communally nesting bird.
Ibis: international journal of avian science, 160(1) pp. 173–178. |
| 50473 |
label |
Portugal, Steven J.; Bowen, James and Riehl, Christina (2018). A rare mineral, vaterite,
acts as a shock absorber in the eggshell of a communally nesting bird. Ibis: international
journal of avian science, 160(1) pp. 173–178. |
| 50473 |
Title |
A rare mineral, vaterite, acts as a shock absorber in the eggshell of a communally
nesting bird |
| 50473 |
in dataset |
oro |