Navigation Links
Competition between females leads to infanticide in some primates
Date:6/8/2011

An international team of scientists, with Spanish participation, has shed light on cannibalism and infanticide carried out by primates, documenting these acts for the first time in the moustached tamarin (Saguinus mystax). The mothers, which cannot raise their infants without help from male group members, commit infanticide in order to prevent the subsequent death of their offspring if they are stressed and in competition with other females.

"Infanticide is an extreme behaviour, and in most species is used by males to eliminate competitors and make females become sexually receptive more quickly", Yvan Lledo-Ferrer, one of the authors of this study and a researcher in the Psychobiology Department at the Autonomous University of Madrid (UAM) and at the German Primate Centre, tells SINC.

However, in callithrix primates (the primate family that Saguinus mystax belongs to), it is the females that perpetrate infanticide. "Genetic analysis enabled us to show that the mothers themselves take the lives of their own offspring", says Lledo-Ferrer.

The study, which has been published in the journal Primates, observed three different groups of moustached tamarins in the Peruvian forest from 1999 to 2008 in order to determine how help from male members of the group and the absence of competition between females helped to ensure the survival of infants.

The results show that 75% of infants survive when at least three males are helping, but only 41.7% survive if the group has one or two male helpers. With regard to competition with other females, 80% of infants die at less than three months of age if there are two gestating females in the group. This figure falls to 20% if there is only one reproductive female.

Unexpected observations

The scientists were surprised when four infants died within the space of a year and the autopsies carried out did not reveal any pathology that would have compromised their survival. In only one of the unexpectedly observed deaths did the mother kill her own offspring. The rest died "without any help".

"Normally, if infants fall to the forest floor from a height, the group keeps picking it up until the infant no longer has the strength to hold on to its carrier's back. At that point they abandon it on the ground. However, in one of these cases the mother killed her own offspring without it having followed the normal pattern of falling to the ground", the expert explains.

The researchers say that reproductive dominance is not well established in cases where infanticide takes place, and there is competition between females to occupy the dominant position. "This competition leads to high levels of prenatal stress, which can affect the foetus and therefore the viability of the offspring and the mother's milk production", the Spanish scientist points out.

Mothers kill infants that have poor prospects for survival due to the social make-up of the group (low number of helpers and the presence of another gestating female). In the cases observed, "the mother consumed her offspring's brain, thereby obtaining a high-quality supplementary source of nutrients, which somewhat offsets those invested during gestation", says Lledo-Ferrer.

One of the explanations for these acts is that the callithrix are a very unusual kind of primate. They have a cooperative baby care system, in which all the members of the group participate, and raising infants is an "extremely" costly activity the whole group must work together in order to for it to be successful.

In this family of primates, only one female can successfully reproduce in each group, while the rest inhibit their ovulation. They have a six-month gestation period.


'/>"/>

Contact: SINC Team
info@agenciasinc.es
FECYT - Spanish Foundation for Science and Technology
Source:Eurekalert  

Related biology news :

1. Gold nanostars outshine the competition
2. Collegiate Inventors Competition recognizes top student inventors
3. Gender biases in leadership selection during competitions within and between groups
4. Study shows competition, not climate change, led to Neanderthal extinction
5. NTU undergrad is first Singapore champion of an internationally acclaimed engineering competition
6. Leading research agencies announce new international competition: "The digging into data challenge"
7. WWF seeks innovative solutions to bycatch through worldwide competition
8. New York, Florida schools win awards at national student competition
9. Fertilization intensifies competition for light and endangers plant diversity
10. Parascript Technology Wins Online Signature Verification Competition
11. Plants prefer their kin, but crowd out competition when sharing a pot with strangers
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Competition between females leads to infanticide in some primates
(Date:2/27/2017)... 27, 2017   Strategic Cyber Ventures , the ... led a $3.5 million investment in  Polarity , the ... Ventures is DC based and is led by cybersecurity ... . Ron Gula , also a longtime cybersecurity ... in this series A round of funding. This new ...
(Date:2/21/2017)... , February 21, 2017 ... 70 Millionen US-Dollar wachsen. Nach einem Gespräch mit mehr als ... einige Hindernisse zu überwinden gilt, um diese Prognose zu ... ... anderem die Mobilisierung der finanziellen Mittel für die Biobank, ...
(Date:2/10/2017)... Research and Markets has announced the addition of ... Commercial Aspects" to their offering. ... Biomarkers play an important ... selection of treatment as well for monitoring the results. There ... modern medicine. Biochip/microarray technologies and next generation sequencing are also ...
Breaking Biology News(10 mins):
(Date:3/27/2017)... YORK , March 27, 2017 ... developing novel therapies for neurodegenerative diseases, including Alzheimer,s ... that its application to list the Company,s common ... approved by The NASDAQ Stock Market, a unit ... the listing, Neurotrope will ring the Opening Bell at ...
(Date:3/24/2017)... Sinovac Biotech Ltd. ("Sinovac" or the "Company") (NASDAQ: SVA), a leading ... announced that its board of directors has amended its shareholder rights ... 27, 2017 to March 27, 2018. The amendment was not in response ... ... Biotech Ltd. is a China -based biopharmaceutical company ...
(Date:3/23/2017)... ... March 23, 2017 , ... AxioMed ... both viscous and elastic characteristics when deformed, which is identical to how the ... gently absorb compressive forces and return to its natural state along a hysteresis ...
(Date:3/23/2017)... Mass. , March 23, 2017 /PRNewswire/ ... partner to global in vitro diagnostics manufacturers ... of the industry,s first multiplexed Inherited ... disease testing by next-generation sequencing (NGS). The ... were developed with input from industry experts ...
Breaking Biology Technology: