It’s been said often enough to become cliché — it takes a village to raise a child. But how many of us have ever thought about why?That question — why human mothers, unlike most among mammals, rely on help to raise children — has long been a critical one for anthropologists. A new study goes a long way toward an answer.Co-authored by Erik Otárola-Castillo, a fellow in David Pilbeam’s paleoanthropology laboratory in the Department of Human Evolutionary Biology, and Karen Kramer, a professor of anthropology at the University of Utah, the findings suggest that evolutionary changes in birth interval and the time it takes for children to reach independence have combined to put significant pressure on time management, forcing mothers to recruit help from older children, extended families, and the larger community. The research is described in a recent paper in the Journal of Human Evolution.“We use the colloquialism that ‘It takes a village’ quite frequently,” Otárola-Castillo said. “The question we wanted to ask was, ‘At what point does it take that?’ We don’t see this in chimpanzees, but we do in humans. At some point humans shared a common ancestor with chimpanzees — at some point our evolutionary lineages were similar, but when did we change, and why?”“Modern human mothers are very interesting, because they’re unlike mothers of most other species,” Kramer added. “We feed our young after weaning, and others help us to raise our children. But this wasn’t always the case. Deep in the past, mothers likely received no help … so we have to ask why others cooperate with mothers to help them raise their children.”For answers, anthropologists have typically found a window into the past through “traditional societies” — cultures in which there is little access to formal education or birth control, and where people consume the foods they produce and have little or no access to market economies.But in this case, Kramer said, those comparisons simply don’t work.In the past 2 million years, a number of traits — including birth interval and the age at which children are independent — have evolved, meaning that human mothers, even ones living in traditional societies, are vastly different from early human ancestors.“The thing is — all these things evolved in the past … so a ‘modern’ traditional population, with a modern life history of short birth intervals and a very long period of juvenility — that is not an appropriate model to look at how cooperation may have evolved,” Kramer said. “Human mothers have this dilemma — do I take care of my newborn, or do I go out and forage for the food my 7-year-old needs? And this creates the constraints that prompt mothers to need help.”To find an appropriate model, Otárola-Castillo and Kramer had to build one.Using humans’ last common ancestor with apes and current traditional societies as their beginning and end points, the researchers developed a mathematical model to explore how various traits changed and what effect those changes had on mothers’ need for assistance.“So we have these two points,” Otárola-Castillo said. “And the question we asked is, ‘What does that transition look like?’ We simulated an economic problem that would have arisen over the course of human evolution. As mothers became more successful at producing children — had shorter birth intervals and more surviving young — they also had more dependents than they could care for on their own. We wanted to know what combinations of traits required the help of other adults.”What the study found was surprising. Most hypotheses about help for mothers point to other adults. The researchers found that it is the other children who are the most reliable helpers. “For many early life history changes, a mother and her cooperating children are able to support each other,” Kramer said. “Only later in time, when we have more modern life histories — weaning is early, birth intervals are short and juveniles are dependent until older ages — do mothers began to need the help of other adults.”
NN Investment Partners’ head of emerging market debt (EMD) and members of his team have left the Dutch asset manager after it made a responsible investment-related decision affecting their remit.Marcelo Assalin, Marco Ruijer and “a number of key members” of their team from NN IP will join US manager William Blair Investment Management in the first quarter of next year to form a dedicated EMD team, William Blair announced this morning.At NN IP, Assalin was most recently head of the EMD team, and Ruijer lead portfolio manager on its EMD hard currency strategy. Lewis Jones has also left NN IP, where he was lead portfolio manager for EMD local currency.A spokeswoman for NN IP said they had decided to leave after NN IP agreed to “further align” its EMD investing strategy with its beliefs about responsible investing. These are that “responsible investing helps deliver attractive returns for our clients within their risk limits while also contributing to society at large”. In a statement published by William Blair, Assalin said he and his former teammates had “enjoyed the opportunity to build a strong EMD franchise over the years”.He added: “I am delighted to be joining a firm that is client focused, empowers its investment teams, where we will have investment autonomy, and be able to incorporate sustainable factors in a holistic and tailored approach that’s beneficial for clients.”At William Blair, Assalin will report to Stephanie Braming, partner and global head of the asset manager, and serve on her leadership team.Of Assalin and the others joining William Blair, Braming said: “These experienced and successful investors are a strong cultural fit with our partnership, holistically incorporate ESG into who they are as investors and as a team, and are focused on delivering strong client outcomes.”NN IP yesterday announced that Edith Siermann, head of specialised fixed income and responsible investing, had been appointed acting head of its EMD team. It also said it had taken the necessary measures to ensure continuity in the management of EMD mandates and funds.Repeat?NN IP has experience of losing key EMD staff in a short amount of time. In 2013, when the asset manager was called ING Investment Management, the then co-heads of its team were hired by Neuberger Berman, which also poached more than a dozen of their colleagues.NN IP announced the appointments of Ruijer and Assalin in fairly quick succession in 2013 as it moved to rebuild its EMD team. Jerry Brewin joined from Aviva Investors that year as head of EMD, with Assalin replacing him in that position in early 2015.