Skip to main content

Egg size predicts motor performance and postnatal weight gain of Australian Brush-turkey (Alectura lathami) hatchlings

Buy Article:

$50.00 plus tax (Refund Policy)

Abstract:

Birds usually influence offspring survival through the amount of parental care they provide. Megapodes have evolved a different life history. Eggs are incubated by external heat sources, and chicks dig themselves out of their underground nest and live independently of their parents. Egg size is one of the few means by which females can influence chick survival. We found that in the Australian Brush-turkey, Alectura lathami Gray, 1831, eggs and hatchlings varied considerably in size, with a ratio of 1.62 between the largest and the smallest egg. Egg size was positively correlated with hatchling body mass and tarsus length. It also significantly predicted the chicks' motor performance: chicks from larger eggs dug their way out of their underground nest faster and were more active when kept in a resting box and monitored by motion detection software. The main advantage of reaching the surface more quickly is likely that such chicks will have more time to find suitable food, refuge, and a tree for roosting at night while still feeding on their internal yolk reserves. Egg size also interacted significantly with body mass during the first 10 months of life. A size advantage at hatching thus seems to have an immediate effect on motor performance and a longer term effect on the ability to gain mass.

L'importance des soins parentaux prodigués par les oiseaux affecte généralement la survie des petits. Les mégapodes ont adopté un cycle biologique différent. Les oeufs sont incubés dans des sources externes de chaleur et les oisillons se creusent une issue de leur nid souterrain et vivent indépendamment de leurs parents. La taille des oeufs est l'un des rares moyens par lesquels la femelle peut affecter la survie de ses oisillons. Chez le talégalle de Latham, Alectura lathami Gray, 1831, les oeufs et les nouveau-nés varient considérablement en taille, le rapport entre le plus grand et le plus petit oeuf atteignant 1,62. La taille de l'oeuf est en corrélation positive avec la masse corporelle du nouveau-né et la longueur de son tarse. Elle permet aussi de prédire la performance motrice des oisillons: les oisillons issus des oeufs plus gros sortent plus rapidement des nids souterrains et sont plus actifs dans des enceintes de repos d'après les enregistrements au moyen de logiciels de détection de mouvements. L'avantage principal d'atteindre la surface du sol plus rapidement est que les oisillons ont plus de temps pour trouver de la nourriture et un refuge adéquat et pour dénicher un arbre pour se percher la nuit, alors qu'ils se nourrissent encore de leur réserves internes de vitellus. Il y a aussi une relation significative entre la taille de l'oeuf et la masse du corps durant les 10 premiers mois de vie. Une taille plus grande à l'éclosion semble donc avoir un effet immédiat sur la performance motrice et un effet à plus long terme sur la capacité d'accroissement de masse.[Traduit par la Rédaction]

Document Type: Research Article

Publication date: 2004-06-01

More about this publication?
  • Published since 1929, this monthly journal reports on primary research contributed by respected international scientists in the broad field of zoology, including behaviour, biochemistry and physiology, developmental biology, ecology, genetics, morphology and ultrastructure, parasitology and pathology, and systematics and evolution. It also invites experts to submit review articles on topics of current interest.
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Terms & Conditions
  • Sample Issue
  • Reprints & Permissions
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more