Parental reactions to a dying marmoset infant: conditional investment by the mother, but not the father

The reproductive costs of cooperatively breeding callitrichid mothers are remarkable, and they have to rely on fathers and other group members to raise their offspring. Consequently, maternal responsiveness to and investment in infants tends to be conditional, and especially sensitive to infant cues and signals of vigour. Since fathers do not bear the same excessive reproductive costs, their threshold to invest in a dying immature may be lower than in mothers. We present an anecdotal report of reactions of a first-time breeding pair of captive common marmosets (Callithrix jacchus) to their dying infant. We found a male bias in all interactions with the dying infant that did not show typical cues of infant vigour. These results show that the dying infant elicited more investment by the father than the mother. Because of this conditional maternal investment, infants of cooperatively breeding primates may be under selection to advertise their viability, in particular to their mothers.

Active sharing of a novel, arbitrary innovation in captive cotton-top tamarins?

Most cultural behaviours in primates stem from innovations that are beneficial since they provide access to food or comfort. Innovations that are seemingly purposeless and arbitrary, and nevertheless spread through a social group, are rarer but particularly relevant to understanding the evolutionary origin of culture. Here, we provide an anecdotal report of a series of non-instrumental woodchip manipulation and modification events in captive cotton-top tamarins. Intriguingly, woodchips were preferentially manipulated in a position that was readily visible to a partner in a different enclosure, and the innovation apparently spread to other individuals. Together, this suggests that the arbitrary innovation was actively shared with a conspecific, which is consistent with the pattern of transmission of another arbitrary innovation in cotton-top tamarins, namely stick-weaving.

US Food and Drug Administration (FDA) Emergency Use Authorization: Glass Half Full or Glass Half Empty?

Recently, the US Food and Drug Administration (FDA) issued emergency use authorization (EUA) for convalescent plasma (CP) for the treatment of hospitalized patients with coronavirus disease 2019 based on a non–peer-reviewed, open-label, observational study. Issuance of an EUA without a proven randomized, controlled trial (RCT) sets a dangerous precedent since the premature action drives healthcare providers and patients away from RCTs that are essential for determining the efficacy and safety of CP. More caution should have been taken based on what was learned from the recent debacle related to the rescinded EUA of hydroxychloroquine and chloroquine, which were approved initially based on an anecdotal report. The FDA process for determining efficacy and safety must be based solely on data from RCTs in order to sustain public and professional trust for future treatment and vaccine efforts to be successful.

Passive Inhalation of Cocaine

Recent studies (1, 2) have shown that dermal absorption of cocaine can lead to low concentrations (<150 μg/L) of the cocaine metabolite benzoylecgonine in urine. An anecdotal report (3) suggests that children may exhibit positive urine cocaine metabolite tests after passive exposure to the vapor created by free-base cocaine smoking.

Corporal Punishment

To the Editor.— The article "Hypovolemic Shock in a Child as a Consequence of Corporal Punishment"1 prompted me to reflect on several points. In their discussion and summarizing sentence, it is clear that the authors oppose any form of corporal punishment. I am concerned that this conclusion is based solely on the perceived risks (adverse effects, as evidenced in this anecdotal report) of physical punishment with no attempt to examine or study any potential benefits of physical punishment.