Dr. Damian Sendler Climate Change Behavior's Evolutionary Psychology
Damian Sendler: An evolutionary psychology lens is used to focus on factors that motivate or discourage people from acting sustainably in order to lessen the effects of climate change on their behavior. We discuss five key ancestral psychological motivations that fundamentally shape people's environmental decisions in addition to what is currently known. We review recent studies that explore how evolved psychological mechanisms related to self-interest, status, sensing, discounting tendencies, and social imitation can be used to promote proenvironmental behavior. We discuss the potential strengths and limitations of evolutionary-based behavioral interventions and briefly reflect on outstanding research questions that can further the integration of evolutionary approaches into mainstream environmental psychology.
Damian Jacob Sendler: Climate change is likely to have devastating social, health, and environmental consequences [1]. However, reducing anthropogenic greenhouse gas emissions [2] could mitigate these effects. Although many lifestyle choices have the potential to reduce personal annual emissions [3], getting people to act in proenvironmental ways is not an easy task. Indeed, despite many people declaring to be concerned about climate change [4], only a fraction engage in sustainable actions [5].
Dr. Sendler: The gap between proenvironmental attitudes and behaviors is commonly observed [6,7]. Researchers in the fields of social and environmental psychology have worked hard to close this knowledge gap [8]. In spite of this, the majority of these studies have focused on more immediate motivations like environmental values, social norms, and monetary rewards. Yet, it is also important to figure out where these motives come from and in what contexts they are relevant. Therefore, the current piece aims to add to the literature by taking an evolutionary psychology perspective on environmental behavior, asking questions about the deeper motives driving people's environmental choices and how people can be "nudged" to behave more sustainably.
Many of our psychological and behavioral tendencies, according to evolutionary psychology [12], have been shaped by natural selection to serve a functional purpose. Adaptations such as our taste for sugary or fattening foods have been passed down from our ancestors because they allowed them to thrive during periods of low calorie availability [12,13]. Adaptation strategies may be less effective if they don't match the ancestral motivations driving the problematic behavior, according to evolutionary psychology [13]. For instance, educating people to avoid junk food because it affects their health may be less effective than making vegetables and fruits taste sweeter. Thus, by studying the relevant ancestral motivations that guide people’s environmental choices, we may be able to come up with new interventions [14]. Admittedly, using an evolutionary lens is a relatively recent approach to study environmental behavior, but it is already generating a reliable body of knowledge. Yet apart from a few notable exceptions [[15], [16], [17], [18]], there has not been a review of the recent literature, which we attempt to do here.
Organisms are adapted to prioritize their outcomes over those of others, and humans are no exception. Many people's environmental decisions are driven by self-interest [16]. Yet, in the long run, people’s self-interests can jeopardize collective efforts to mitigate climate change. It is clear that the only way to address climate change is for countries (and their citizens) to do what's right in the interests of the whole and commit to reducing their emissions drastically [32]. However, while cutting down emissions might seem rational from a collective perspective, asking people to depart from doing what is good for them is exceedingly difficult. We might need to do the opposite, according to evolutionary literature, which suggests that people's self-interest can be used to motivate environmental action [33].
Known as kin selection theory [20], inclusive fitness theory [19] proposes that people have a natural tendency to protect the genes they share with their kin in order to ensure their long-term survival and reproduction. Individuals, therefore, are likely to cooperate more with those that share more of their genetic makeup. In terms of motivating proenvironmental action, this suggests that people will change their behavior if their long-term genetic interests are at stake. Activating kin care motivations by emphasizing the negative effects of environmental problems on their children (i.e., their genetic future) has been shown to increase environmental intentions in previous research[34]. Similarly, emphasizing self-interest — either economic, health-related, or genetic — has been shown to reduce drivers’ engine idling at long wait stops [21∗], and persuasive strategies using kinship-based appeals positively influence animal conservation efforts, especially among those who express low levels of environmental concern [35]. This last finding is significant because it illustrates the potency of kinship-based arguments in court. Many recent models suggest that appealing to people's self-interest rather than the global environment is a more effective way to get them to act on climate change [33].
Damian Sendler
In most species, attaining status and higher social rank is linked with many evolutionary benefits [36]. In this respect, humans are no different [37,38]. Because of this, our psychology is likely to have evolved to be motivated to seek and display status [39]. Human social status may also serve as a signal of a person's relevant underlying characteristics, according to the costly signaling theory, which claims that organisms develop costly traits in order to signal their non-directly observable qualities to potential partners [22]. Although social status is often communicated via displays of wealth, some research lines have pointed out that behaving cooperatively and sustainably could also help individuals to attain and signal status [41,42,43∗], and thus, interventions based on status motives might encourage people to ‘keep up with the environmentalists’.
Consumers' perceptions of their social status rise when they use sustainable products, according to new research ([41], but see Ref. [44]). Contrary to early findings (e.g. Ref. [42]), this is not affected by product price but rather linked to people’s perceptions that sustainable consumers are more prosocial [41]. Importantly, people favor environmentalists as social partners because they not only see them as more prosocial, but they also perceive them as more prosocial themselves [43]. Similarly, in romantic contexts, communicative signals of a proenvironmental lifestyle increase the romantic attractiveness of senders. Both men and women tend to rate opposite-sex individuals as more attractive long-term partners — and to a lesser extent, short-term ones [45] — when they consume sustainable products [46], and (men) owners of such products are perceived to be altruistic and committed parents and partners [47∗].
Admittedly, most of these findings rely on perceptions and expectations of the signalers’ behavior rather than actual behavior. People who identify as environmentalists, for example, are expected to be more cooperative, but their contributions to experimental public goods games are no greater than those of the general public [43]. According to some, the (lack of) visibility of the cooperative act is to blame for the discrepancy in cooperative behavior expectations. People are more willing to pay more for environmentally friendly products, even if they are more expensive, if the decision is made publicly [48]. Donations to environmental charities go up when people are aware of them, and they go up even more when people who will be interacting with them in the future are aware of them [23].
Damian Jacob Markiewicz Sendler: In many people's minds, climate change is a long-term problem that won't have any immediate impact because of our highly developed, acute threat detection system. People usually only become aware of such problems via modern information channels. Ancient peoples, on the other hand, evaluated potential environmental threats based on immediate environmental cues (such as a drought or bushfire). According to evolutionary mismatch theory [13], the global and slow-moving nature of climate change fails to activate an immediate self-protection response, making it less likely for people to adapt their behaviors. The mismatch can be overcome by increasing the effectiveness of environmental communications by providing immediate cues that can be detected through our primary sensory mechanisms — through smells, vision, and sound. For instance, energy research shows that visualization of thermal energy increases householders’ willingness to engage in energy-saving behaviors [49,50]. Sensory information, according to research, may also aid in the cleanup of public spaces and the reduction of plastic pollution. Just the smell of cleaning products in trains decreases littering [51], and consumption of bottled water is likely to decrease if subjective judgments of tap water taste and odor are improved [52].
Damian Jacob Sendler
Climate change actions can also be triggered by evolutionarily old emotions that humans experience via their physical senses. Disgust-based persuasive strategies, in particular, appear to be an effective way to activate self-protection needs in order to modify unsustainable eating patterns [53]. For instance, pairing meat products with evolutionary relevant threats such as pathogens negatively affects attitudes to consume meats [25∗]. At the same time, feelings of disgust are an important obstacle to overcome for the acceptance of sustainable food innovations such as lab-grown meat [54] and edible insects [55]. For example, recent developments on the study of acceptance of lab-grown meat show that its perceived unnaturalness elicits feelings of disgust, which, in turn, reduces the willingness to consume and buy it [54].
In many organisms, such as humans, temporal discounting refers to the preference for near-term rewards over those that are more distant and uncertain [26,56]. Because delaying rewards increases the likelihood that these benefits will be unavailable in the future, our psychology has evolved to place a lower value on future gratification when making decisions [26]. This tendency to discount the future, however, might interfere with environmental policies requesting people to behave sustainably to prevent potentially adverse environmental outcomes of climate change. A recent study showed that people report less concern about and willingness to prevent an environmental issue when the issue is phrased as occurring later in time, further away, and when there is less certainty that the environmental issue will eventually happen [57∗]. Similarly, activating feelings of uncertainty in people makes them discount the future more in their environmental decisions [58∗].
Damien Sendler: People prefer immediate gratification to delayed gratification [59], but this preference is influenced by environmental cues and situational factors (e.g. Ref. [27]), both of which can be influenced by climate change interventions. For instance, regular exposure to nature — compared to exposure to urban environments — reduces temporal discounting rates [60,61]. Importantly, recent research suggests that this may have implications for environmental decision-making. There is a preference among people to wait longer before breathing cleaner air when shown images of natural environments [29].
It's no secret that people are social creatures. As resource scarcity and uncertainty probably characterized the environments in which ancestral humans lived, adaptations to copy, learn from, and follow others are likely to have provided them with many evolutionary advantages [62]. Indeed, cultural evolution theories posit that social learning evolved to minimize the costs of trial-and-error learning [63]. However, when it comes to taking action to combat climate change, following in the footsteps of others could prove counterproductive. Descriptive social norms — that is, norms based on perceptions of what most others are doing — can be effective in promoting sustainable behavior when the majority of people indeed behave sustainably (e.g. Ref. [64]), but the opposite happens when the majority does not. For instance, the presence of others can sometimes increase people’s tendency to over-purchase food and lead to greater food waste [65]. But our innate tendency to imitate others and emulate role models can be harnessed to help us take action on climate change. People are more likely to prioritize addressing climate change when there is a greater sense of scientific consensus about it [66]. Describing norms is associated with taking action to combat climate change, according to meta-analysis [31]. Similarity and ingroup bias are also factors that influence the behaviors that people mimic. People are more likely to reduce their energy consumption if they feel like they belong to a group that is concerned about climate change, as evidenced by research showing that conservative and liberal voters who believe in climate change are more likely to share this belief [67].
Although each of the aforementioned ancestral motivations provides potential venues to develop interventions to increase climate action, they must be activated in the right context to be effective. Take the status-motive, for instance. In an effort to attain a green reputation, people, in some cases, purchase more recyclable shopping bags than they really need [69]. Signaling a green reputation might be more relevant for certain people [70], and people are more inclined to show off their green credentials in public settings [71]. It is therefore necessary to consider the contexts, behaviors, and people targeted by these ancestral motivations when developing effective interventions. This is because effective interventions are based on these ancestral motivations. Failing to reflect on these issues might diminish the interventions’ impact, or even be counterproductive.
An evolutionary psychology lens was used to study climate-relevant behavior, and the results are summarized in this short article. Although much has already been achieved, multiple research questions remain unanswered. Observing your children's disgust at meat consumption, for example, could harnessing two evolved mechanisms at the same time be beneficial for an intervention? Moreover, future research could also study interventions — and their impacts — longitudinally, as done elsewhere in the context of the impact of greening schoolyards on children’s social and cognitive development [72]. Finally, because most of the research we've discussed has used self-reports, it's important to know how these effects translate to actual behaviors. These and other questions are, to our thinking, of utmost importance for the integration of evolutionary approaches into mainstream environmental psychology.