It’s the end of the year and I find myself absolutely swamped by the large number seriously cool science stuff. Most of it is admittedly in psychology and sociology.

• Starting with something in the harder sciences, here’s an article about how amoebas seem to be able to find an approximate solution to the famous Travelling Salesman Problem (TSP), an NP-hard problem, in linear time. The experiment involves growing amoebas growing in a medium. The amoeba wants to grow towards agar but also avoid light. By manipulating the light can simulate distances between cities in the TSP. The system is much slower than conventional computers since amoebas move slowly but it’s intriguing to think whether or not such a setup can be scaled up.
• Mammals are known for secreting milk to suckle their young but this next article talks about a species of spider that does something similar. The mechanisms are completely different, with the nutritious fluid being secreted from the canal that the female spider lays eggs. Observations however show that the young spiders are completely dependent on it for nutrition 20 days after hatching and though they are able to leave the nest to find food on their own after that, still partially depend on the fluid until about 40 days after hatching. It’s a good reminder that nature is much weirder than we think and mocks at our arbitrary systems for classifying organisms.
• Next up are fruit flies and what has been billed as a very primitive form of culture in their behavior. After adding artificial colors to male flies the researchers allowed female flies to watch other female pick mates. They found that those females were much more likely to later pick mates of the same color that they had seen the previous females choose. More interestingly, this preference persisted in subsequent generations.
• Then we move on to people. Facebook has been in the news a lot lately and at least part of the debate involves how much value it generates for its users to see if that justify the costs in terms of data leakage risks and other dangers. However traditional methods of valuing the service is difficult as it is free so instead researchers have turned to asking how much would they need to be paid in order to give it up for a year. This particular survey found that the average Facebook user would need to be paid US$1,000 in order to agree to deactivate their account for a year.
• Academics are well known to lean leftwards and be more skeptical of markets. One hypothesis is that markets are only contingently sensitive to school achievement, leading academics to be disappointed that their success in school is only imperfectly correlated with economic success. This survey of 1,500 French academic respondents claims to find evidence that this is true.
• The next article surveys a mixture of millennials and older people in order to test the ability of older people to discern the truth. Specifically, the respondents were instructed to tell a lie first and some time later were asked their own opinion on the topic. They found that older adults were more committed to the lie that they first told, as if the lie becomes embedded in their memory and becomes the truth.
• Finally, let’s end this with a paper that should really be read in its entirety to get it read but to roughly summarize it asks the question of whether cultural values and opinions in a society change over time due to people changing their minds as they get older or because the people who hold older values die off over time. The paper crunches data from a large General Social Survey in a way that I can’t pretend to understand to conclude that the effects of the latter dominate, that is overall opinions change because the people who held them die over time.