Related Experiment Video
Updated: Jun 30, 2026
04:56
An Efficient Single-Person Technique for Milk Sampling from Laboratory Mice
Published on: March 28, 2025
Time and energy constraints in pinniped lactation
1British Antarctic Survey, Natural Environment Research Council, Cambridge CB3 OET, United Kingdom.
The American Naturalist
|September 25, 2008
Summary
Pinniped lactation strategies depend on body mass, not just phylogeny. Larger species rely on body reserves and forage widely, while smaller ones forage locally, adapting to prey availability.
Area of Science:
- Marine Mammal Biology
- Ecology and Evolutionary Biology
- Physiological Ecology
Background:
- Pinniped lactation patterns have been historically linked to phylogenetic relationships.
- Previous models did not fully integrate the energetic demands on lactating mothers.
Purpose of the Study:
- To extend existing pinniped lactation models by incorporating comprehensive energetic costs for mothers.
- To investigate the influence of body mass on feasible lactation strategies in pinnipeds.
Main Methods:
- Analysis of time-energy budgets to model lactation strategies.
- Evaluation of foraging ranges and prey resource quality in relation to body mass.
Main Results:
- Lactation strategy feasibility is strongly dependent on species' body mass.
- Large pinnipeds typically rely on body reserves for lactation, foraging over extended ranges.
- Small pinnipeds forage locally, often near pupping colonies, due to higher metabolic maintenance costs.
Conclusions:
- Body mass, rather than phylogeny, appears to be a primary driver of pinniped lactation strategies.
- Pinniped lactation evolves as adaptive solutions to trade-offs between foraging range and prey resource availability.
- Adaptation plays a more significant role than phylogeny in shaping pinniped lactation.
Related Concept Videos
00:51Energy Budgets and Reproductive Strategies
Organisms must balance energy intake with the energy required for growth, maintenance, and reproduction. These trade-offs result in a variety of survivorship and reproductive strategies, including semelparity and iteroparity. Semelparous species reproduce only once in their lifetime, often investing most available resources into that single reproductive event. Iteroparous species, by contrast, reproduce multiple times over their lifetimes, typically allocating fewer resources to any single...
00:55Parental Care
Many animals exhibit parental care behavior, including feeding, grooming, and protecting young offspring. Parental care is universal in mammals and birds, which often have young that are born relatively helpless. Several species of insects and fish, as well as some amphibians, also care for their young.
01:01Production Efficiency
Net production efficiency (NPE) is the efficiency at which organisms assimilate energy into biomass for the next trophic level. Due to low metabolic rates and less energy spent on thermoregulatory processes, the NPE of ectotherms (cold-blooded animals) is 10 times higher than endotherms (warm-blooded animals).
01:12The Mammary Glands
The female breast is a hemispheric projection of variable size positioned anterior to the pectoralis major and serratus anterior muscles. A fascia layer composed of dense, irregular connective tissue connects it to these muscles.
Each breast features a pigmented projection known as the nipple, through which milk emerges via closely spaced openings of ducts, referred to as lactiferous ducts. Surrounding the nipple is a circular pigmented area of skin named the areola, which appears rough due to...
Each breast features a pigmented projection known as the nipple, through which milk emerges via closely spaced openings of ducts, referred to as lactiferous ducts. Surrounding the nipple is a circular pigmented area of skin named the areola, which appears rough due to...