Among rhesus macaque monkeys, mothers who weigh more and have had previous pregnancies produce more and better breast milk for their babies than mothers who weigh less and are less experienced.
Scientists from the Smithsonian Institution and the University of California, Davis are using this natural variation in breast milk quality and quantity to show that a mother's milk sends a reliable signal to infants about their environment. This signal may program the infant's behavior and temperament according to expectations of available resources and discourages temperaments that prove risky when food is scarce. The study was published in the American Journal of Primatology Feb. 16.
Researchers used large groups of rhesus macaques living in an outdoor enclosure at the California National Primate Research Center at UC Davis. Researchers collected milk two different times from 59 mothers: once when their infants were 1 month old and again when the infants were 3 1/2 months old. They recorded the quantity of milk produced by each mother, and the energy value of each one's milk was analyzed for its content of sugars, proteins and fat. These figures were combined to calculate the available milk energy generated by each mother.
Although all of the monkeys in the study were fed the same diet, the researchers found natural variation in the quantity and richness of the milk generated by the 59 mothers. Milk from mothers who weighed more and had had previous pregnancies contained higher available energy when their infants were 1 month old than the milk of lighter, less experienced mothers.
"This is the first study for any mammal that presents evidence that natural variation in available milk energy from the mother is associated with later variation in infant behavior and temperament," said Katie Hinde, the study's lead author and anthropologist at the California National Primate Research Center and the nutrition laboratory at the Smithsonian's National Zoo. "Our results suggest that the milk energy available soon after birth may be a nutritional cue that calibrates the infant's behavior to environmental or maternal conditions."
At 3 to 4 months old, each infant was temporarily separated from its mother and assessed according to its behavior and temperament. The study found that infants whose mothers had higher levels of milk energy soon after their birth coped more effectively (moved around more, explored more, ate and drank) and showed greater confidence (were more playful, curious and active). Infants whose mothers had lower milk energy had lower activity levels and were less confident when separated from their mother. Mothers and infants were reunited immediately after the experiment.
Rhesus macaques are found throughout mainland Asia: from Afghanistan to India and from Thailand to southern China. A free-ranging colony of rhesus macaques was established in 1938 on Cayo Santiago—a small island off of the east coast of Puerto Rico. The only primates with a broader geographic distribution than rhesus macaques are humans.
To learn more about this and other Smithsonian research visit: http://smithsonianscience.org/
What happens in the cell nucleus after fertilization
06.12.2016 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt
Researchers uncover protein-based “cancer signature”
05.12.2016 | Universität Basel
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
06.12.2016 | Materials Sciences
06.12.2016 | Medical Engineering
06.12.2016 | Power and Electrical Engineering