This is an article that Jesse Clifton, Jacy Reese and myself wrote in 2016 to summarise the current literature on effective animal advocacy. While the paper was unsuccessful in journal submission as it broke no new ground, the reviewers suggested (and we agreed) that it was a useful summary and would be valuable to have in the public domain.
Whether you are new to effective animal advocacy or experienced, we hope you will get good use out of this literature review.
For a pdf version of this article, please click here.
Michael Dello-Iacovo, Jesse Clifton & Jacy Reese
Written in 2016
Effective animal advocacy combines animal advocacy and Effective Altruism, a philosophy and social movement that applies evidence and reason to determining the most effective ways to improve the world. We review the effective animal advocacy literature, including the psychology of animal product consumption and behavioural change, the effectiveness of various interventions on behalf of animals, the prospects of animal product alternatives to help animals, wild-animal suffering, and meta-level animal advocacy strategy. We highlight interventions and areas of research which appear to be promising and neglected targets of marginal resources in effective animal advocacy. While it is premature to conclude which strategy is the most effective at reducing animal suffering, Animal Charity Evaluators has suggested that corporate outreach and undercover investigations are two of the most promising direct interventions identified thus far. Helping and spreading concern for wild animals is also a neglected area of research given the scale of suffering in the wild. Meta-strategies, such as movement-building and promoting pro-giving behaviour amongst animal advocates, may be more effective than conventional animal advocacy.
Effective animal advocacy is the use of evidence and reason to find and implement the most effective ways to help nonhuman animals. It lies at the intersection of the animal protection movement, which seeks to reduce the harm and injustice suffered by nonhuman animals, and Effective Altruism, a philosophy and social movement that applies evidence and reason to determining the most effective ways to improve the world. Here we review the research on effective animal advocacy, including:
- the psychological literature relevant to animal product consumption and persuading people to change their diets;
- estimates of the impact on animals of creating additional vegetarian/vegan1 (veg*n hereafter) or meat reducers;
- surveys and experiments on effectively causing dietary change;
- observations on the effectiveness of other interventions to change social attitudes and behaviours related to animals, such as undercover investigations of factory farms;
- observations on the effectiveness of campaigns to change corporate and public policy;
- notes on the current state of cellular agriculture and plant-based food technology and their prospects for reducing animal suffering;
- research on possible interventions to help animals suffering in the wild;
- observations on meta-level activities, such as increasing the size and effectiveness of the animal advocacy movement.
While modern animal activism emerged approximately in the 1960s and efforts to help animals date back to at least the first millennium BCE (Phelps 2007), effective animal advocacy per se is a young field. Faunalytics (originally the Humane Research Council) was founded in 2000 to conduct research intended to inform animal advocacy, and Animal Charity Evaluators (ACE; originally Effective Animal Activism) was founded in 2012 to identify the most cost-effective animal nonprofits and conduct other research on effective animal advocacy. Since then, several organizations have emerged in the effective animal advocacy space, including Humane League Labs, which was founded in 2013 to research the most effective animal advocacy strategies; and Sentience Politics, an anti-speciesist political think tank founded in 2013 which conducts research on effective farm animal advocacy as well as wild-animal suffering. Effective animal advocacy conferences include the Sentience Conference, the first of which was sponsored by Sentience Politics in May 2016, The 2016 Symposium on Multidisciplinary Research in Effective Animal Advocacy, the first of which was sponsored by ACE in November 2016, and the annual Effective Altruism Global conference, which includes effective animal advocacy as a major theme.
Effective animal advocates are largely focused on farmed animals. ACE justifies its emphasis on farmed animals as due to the scale of suffering faced by farmed animals (tens of billions of land animals alone are raised on factory farms and killed each year), the neglectedness of farmed animal welfare (only 1% of donations in the U.S. to animal charities go to those who work specifically on farmed animal issues, meaning that only 0.015% of all donations in the U.S. go to work on farmed animals; Bockman 2016), and the tractability of solutions (we can make substantial progress on the issue with reasonable amounts of resources; Bockman 2016). Some effective animal advocacy organizations also promote concern for or research interventions to relieve the suffering of individual wild animals, due to the scale and neglectedness of this problem (ACE n.d.a; Sentience Politics n.d.a). Historically, animal advocates have largely focused on vertebrates, though Tomasik (2007, 2015a) and Sentience Politics (Sentience Politics n.d.b) discuss the moral importance of invertebrates and suggest possibilities for helping insects.
This report will not fully cover the moral arguments surrounding the treatment of animals, but we note that effective animal advocacy is largely consequentialist in ethical orientation. See Armstrong and Botzler (2008) for a collection of readings on animal ethics.
- Psychology of Animal Consumption and Behaviour Change
Understanding the psychology of animal product consumption is important in designing effective strategies for convincing the public to consume fewer animal products (Zur and Klöckner 2014; Schösler et al., 2012). Loughnan et al. (2014) and the references therein introduce psychology of eating animal products, and Amiot and Bastian (2014) review the psychology of human-animal relations more generally.
The “meat paradox” refers to the fact that individuals express concern for animals while consuming meat or other animal products, often knowing that the production of these foods caused considerable animal suffering. People who consume animal products are able to reduce this cognitive dissonance by perceiving animals as less capable of experiencing suffering, especially food animals (Rothgerber 2014; Bastian et al., 2011). Joy (2010) discusses the apparent contradictions in people’s attitudes and behaviours towards animals, and develops the concept of carnism, a belief system which conditions society to eat the products of certain animals. Piazza et al. (2015) found that the vast majority of justifications for eating meat given by study participants fell under the “4Ns” classification: meat eating is natural, normal, necessary, and nice-tasting.
Bastian and Loughnan (2016) suggest that interventions to reduce prejudice have varied success, as individuals find ways to resolve feelings of discomfort when their identities are being threatened, and may even reinforce negative attitudes. In Loughnan et al. (2010), study participants rated animals as less capable of suffering after consuming meat.
2.1 Outreach Targeting
Animal advocates may want to target their outreach towards demographics most likely to be receptive; for instance, animal advocacy groups often target online ads towards young women, who are thought to have higher rates of veg*nism and concern for animal welfare (ACE n.d.b). The following traits have been suggested as predicting higher rates of veg*nism:
- Female (Rothgerber 2012; Cooney 2014)
- Young (Cooney 2014)
- Liberal political orientation (Allen and Ng 2003)
- LGBT (Cooney 2014)
- Single (Cooney 2014)
- Intelligent (Cooney 2014)
- Artistic (Cooney 2014)
- Introverted (Cooney 2014)
- Live in a big city (Cooney 2014)
- Don’t follow a Judeo-Christian religion (Cooney 2014)
- Openness to experience (Keller and Siegrist 2015; Graça et al., 2016)
- Disapproval of hierarchy and inequality (Mõttus et al., 2012)
2.2 Behaviour Change
The most effective messaging for effecting dietary change is a topic of debate among animal advocates. The ‘foot-in-the-door’ (FITD) technique (Freedman and Fraser 1966) is used in a range of settings to promote a major behaviour change by first making a smaller and more manageable request. A large body of evidence on FITD suggests that incrementalist strategies (e.g. asking people to reduce their meat intake) could be more effective than asking people to go fully vegan (N. Cooney pers. comms. 2016). However, another technique used to promote behaviour change is the ‘door-in-the-face’ (DITF) technique (Cialdini et al., 1975), which involves making a large request (with the expectation that it will be turned down) followed by a smaller request, which the respondent is then more likely to accept. This might involve asking someone to go veg*n, followed by asking them to reduce their meat consumption. In a meta-analysis, Pascual and Guéguen (2005) found that the effectiveness of the FITD and DITF techniques were similar, and Dolinski (2011) has suggested that combining both methods (termed the ‘foot-in-the-face’ (FITF) technique) may also be effective.
2.3 Additional Considerations
Several key considerations have not been studied in rigorous experiments (although some are covered to an extent in less rigorous fora such as blogs). The most effective line of messaging for reducing animal suffering (e.g. veg*n vs reducetarian, welfarism vs abolitionism) in particular has not been well explored.
It is worth noting that much published psychological research is not reproducible in lab conditions (Open Science Collaboration 2015). This poses concerns for the internal validity of psychological research relevant to animal advocacy, as well as the transfer of these findings to animal advocacy settings. Animal advocates interested in using quantitative research to inform their strategies should examine studies for statistical power and evidence of p-hacking and forking paths (Gelman and Loken 2013).
- The Impact of Additional Vegetarians or Vegans
Persuading people to eat fewer animal products is a major goal of many animal advocates. Here we examine the effects of individual dietary change on animal welfare.
The average meat-eating American is expected to consume about 30 land animals each year, including 28 chickens (Sethu 2012). The number of marine animals consumed is harder to estimate, and there is a large number of by-kill associated with the fishing industry, with some estimates suggesting between 0.97 and 2.7 trillion wild marine animals killed globally each year (Mood and Brooke 2010). ACE estimates that the number of farmed fish eaten per capita each year in the United States is 2-3 (ACE n.d.c). Including wild fish eaten as well as those caught to feed farmed fish, ACE (n.d.c) estimates annual per capita consumption as 46-79, with an additional 186 shellfish per year, most of which are shrimp.
Approximately two egg-laying hens are needed to feed the average egg-eating American each year, while one cow is required to meet the dairy consumption of 30 Americans on average (Norwood and Lusk 2011). Each year, one lab animal is experimented on in the United States for every 15 Americans (The Humane Society n.d.; US Department of Agriculture n.d.). Around 1 animal is killed for their fur each year per 100 Americans (Fur Commission USA n.d.). Animals are also killed in the process of crop production; Matheny (2003) estimates that at least 0.3 animals (not including invertebrates) are killed each year in the process of producing crops for the average American vegan. In the remainder of this section we focus on the effects of animal food product consumption, as this is the priority of most effective animal advocates.
But the purchase of one fewer animal product does not necessarily result in the production of one fewer product. Estimates on effects that changes in consumer behaviour have on the number of animals raised (or killed, in the case of wild-caught marine animal consumption) for food must account for the sensitivity of the market to changes in the quantity of animal products demanded and supplied (i.e. the price elasticities of demand and supply). Using elasticity estimates, ACE estimates that one person consuming 30 fewer land animals will result in 1.8 – 21 fewer animals being farmed, and one person consuming 232 fewer marine animals results in 35 – 144 fewer being killed (ACE n.d.d). The long-term effects of sparing marine animals are unclear, both on the individuals spared (who will die a possibly painful natural death) and on the entire food chain (Tomasik 2015b). The land animals, mostly farmed, will not be brought into existence in the first place. As animal advocates generally believe that farmed animal lives are not worth living given the suffering they experience, causing fewer to be born is considered an improvement (Matheny and Chan 2005).
Norwood and Lusk (2011) rate farmed animal welfare on a scale of -10 to +10, which rates beef cows, dairy cows, and broiler chickens as having lives worth living. Their ratings have been criticized as overestimating farmed animal well-being; Sara Shields of the Humane Society of the United States provides her own rating in which most animals are scored much lower (Ball 2014).
Creating additional vegetarians and vegans can have additional long-term effects, whose benefits to animals are more difficult to assess. Dietary change may be associated with other changes in attitude and behaviour, such as activism. Dietary change may also have significant impacts on wild animals, but whether this is are net positive or negative is far from clear. Fewer farmed animals leads to reduced greenhouse gas emissions, potentially slowing climate change, whose net effects on wild-animal suffering are very difficult to determine. Tomasik (2013a) points out that reductions in animal farming are likely to lead to the return of farmed land to wilderness, with higher concentrations of wild animals. Moreover, it is possible that veg*n outreach contributes to environmentalist attitudes, thereby which harm animals via increased wilderness preservation and the prevention of humanitarian intervention in nature (Tomasik 2015c). Hecht (2016) finds some support for the hypothesis that environmentally-focused, but not cruelty-focused, veg*n outreach dampens concern for wild-animal suffering and willingness to intervene in nature to reduce suffering. If wild animal lives are in general not worth living (see below in Wild-Animal Suffering), it is possible that the net effect of dietary change on animal suffering is much less positive than is suggested by estimates which do not account for wild animals. Further work should be done to examine the effects of various flow-through effects on the total amount of good done by encouraging dietary change.
3.1 Additional Considerations
3.1.1 Relapse Rate of Dietary Changes
Not everyone who becomes veg*n remains veg*n; estimating the impact of dietary change requires estimating how long the average veg*n maintains this diet. Studies using self-reporting suggest that the average converted vegetarian will stick to this diet for an average of seven years (ACE n.d.e). Faunalytics (2014) estimates that there are five times as many former vegetarians as current vegetarians in the US (10% of Americans compared to 2%), while Alfano (2005) suggests that there are three times as many. None of these studies followed participants after a particular intervention or examined the reasons why people went vegetarian. Since the length of time the diet is adhered to may vary depending on the intervention which led to the dietary change, this is a major gap in the literature. Self-reported former vegetarians may consume less meat than those who have never been vegetarian (Haverstock and Forgays 2012), though other studies have found this to not be the case (Barr and Chapman 2002).
Using data from Faunalytics (2014), ACE examined the cost-effectiveness of retention programs to reduce veg*n recidivism, and concluded that they are unlikely to be as effective as traditional forms of outreach such as leafleting. They do note that targeting individuals most at risk of recidivism may improve the effectiveness of the intervention (Adleberg 2016).
3.1.2 Bias in Dietary Self-report
Interestingly, Haddad and Tanzman (2003) found that 64% of individuals identifying as vegetarians also reported eating a non-vegetarian food item in the last 24 hours in one or both of two sample times. Therefore it is standard practice to also ask surveyees to estimate their meat consumption in the last few days. Social desirability bias, the tendency of survey respondents to answer in a way they think will be viewed favourably (Grimm 2010), is also likely to cause respondents to understate their consumption of animal products in dietary self-reports (ACE (2013) found that reported meat consumption was negatively correlated with a measure of social desirability, and this negative relationship was stronger in the group who had received vegan outreach leaflets).
The Humane League and Farm Sanctuary measured the effects of vegetarian and reducetarian leaflets on approximately 450 college students’ self-reported animal product consumption, finding that nearly one in fifty who reported receiving a leaflet indicated they’d become vegetarian or pescatarian as a result (Cooney 2013b). In a similar study, ACE (2013) found that students who received a vegan leaflet reported statistically significantly higher reductions in red meat and poultry consumption than those who received a control leaflet about puppy mills. Finally, a 2015 Humane League study compared the effectiveness of several types of messaging, finding that those who said they had received no leaflet reported the highest average reductions in consumption of red meat, poultry, and dairy (though not statistically significantly so; Doebel and Gabriel 2015).
Each of these studies suffers from significant methodological shortcomings, such as reliance on self-reports (see Bias in dietary self-reports), high or unreported attrition/no-response rates, and low power due to small sample size. The studies’ estimates of dietary change caused by leaflets may also conflict with actual rates of veg*ism in the population: Wayne Hsiung of Direct Action Everywhere (DxE) argues that if 1-2% of people who received a leaflet went veg*n, we would expect to see hundreds of thousands more veg*ns than we actually do, given that animal advocacy organizations have handed out tens of millions of veg*n leaflets. If true, this would suggest that either studies which find such high rates of success for leafleting are either inaccurate for many of the leaflets used, or recidivism rates for these interventions are very high (Hsiung 2014).
Leafleting is cheap (average of 0.35 USD per leaflet; ACE n.d.f) and requires little training or planning to implement. The studies discussed above provide weak evidence that leafleting is a cost-effective way to cause dietary change. ACE (2013) recommends this intervention for its potential to involve new activists, but encourages groups to also carry out interventions such as undercover investigations and corporate outreach, which appear more effective overall.
As discussed above, the effectiveness of leaflets in effecting dietary change is uncertain due to the limitations of leafleting studies. Moreover, by focusing on individual change, the secondary benefits of leafleting, such as movement building, change in policies and societal attitudes towards animals, may be limited.
4.2 Online Ads
Also used for veg*n outreach are online ads which link to content encouraging the viewer to reduce their consumption of animal products. Facebook is a common location for ads, as it allows for ads targeted to certain demographics thought to be most receptive to veg*n messaging (ACE n.d.b).
Faunalytics (2012) compared ads with environmental, health, and ethics-based messaging, finding that the videos with an animal ethics message were associated with the most reports of intention to eat fewer animal products. The Humane League and Farm Sanctuary studied online ads targeted at young females, finding that the percentage of viewers who ordered literature on vegetarianism ranged from 1.5% to 2.7% (depending on the video shown; Cooney 2013a). Finally, Mercy for Animals (n.d.) studied Facebook ads aimed at women ages 13-25, finding no statistically significant difference in reported diet between the group who was shown a video about farmed animal cruelty and the control group who viewed an unrelated video. In fact, the experimental group reported slightly higher average animal product consumption (Mercy for Animals n.d.). Features such as pre-registration and use of randomized assignment to experimental and control groups make this study the strongest piece of evidence on the effectiveness of a veg outreach intervention; however, it still suffered from low power and unreported attrition.
Online ads can reach many people at low cost (1,000 impressions can be bought for around 0.19 USD). A significant number of users (0.3-3.8%) click on ads, and a significant number (2.6-41.4%) of these enter their email address and pledge to go vegetarian; obtaining email addresses, as well as social media followers, may help to boost activism. Finally, short feedback loops between the implementation of an ad campaign and collecting data on cost-per-click or cost-per-conversion makes it easier for project managers to improve ad content and targeting (ACE n.d.b).
Given the evidence cited above, the effects of online ads on dietary change are unclear. The focus of online ads on vegetarianism or reducetarianism, rather than veganism, may undercut the goal of a complete shift away from animal products. And as with leafleting, the focus on individual behaviour change may have limited positive effects on animal advocacy movement-building and the likelihood of a major shift in social attitudes towards animals, and carries the risk of presenting veg*nism as a personal choice rather than as necessary for society as a whole. ACE does not currently recommend that organizations implement new online ads programs or expand existing ones, at least when these resources could be used for more promising interventions like corporate outreach or undercover investigations (ACE n.d.b).
4.3 Estimated Impact of Leaflets and Online Ads
Using the results of these leafleting, online ads, and veg*n recidivism studies, ACE (n.d.f) estimates an average of 0.01 meat abstainers, 0.006 dairy abstainers, and 0.004 egg abstainers per leaflet; 0.007 meat abstainers and no dairy or egg abstainers per online ad click2; and 7.03 years of abstention by the average animal product limiter. Combining these figures with their estimates of the effect on animals of one person becoming an animal product limiter, ACE estimates that a single leaflet saves, on average, 0.0062 cows; 0.022 pigs; 1.2 chickens; 0.017 turkeys; 0.097 farmed fish; and 2.9 farmed shellfish from being born into commercial farms, and saves 1.1 wild fish and 2.9 wild shellfish from being killed for food, which makes 8.3 animals saved from either a life on a farm or being killed in the wild. Their estimates for a click on an online ad are 0.0039 cows, 0.014 pigs, 0.76 chickens, 0.011 turkeys, 0.062 farmed fish, 1.8 farmed shellfish, 0.72 wild fish, and 1.8 shellfish for a total of 5.2 animals saved (ACE n.d.f).
4.4 Humane Education
In the context of animal advocacy humane education refers to presentations, usually to a young audience (from elementary school to university-level), on issues relating to the treatment of animals. In its review of this intervention, ACE states that it lacks enough information to rigorously evaluate humane education’s effectiveness, but that it is promising and worth further investigation. Existing research includes an ACE analysis of data from study by Justice for Animals which found very weak evidence for the effectiveness of humane education in creating new veg*ns, and a study by ACE which found no effect of humane education on self-reported diet (ACE n.d.g).
4.5 Undercover Investigations
In ACE’s write-up on undercover investigations of factory farms, they list the major strengths of this intervention as its ability to create immediate change through corporate or legal policy reform and through consumers reducing their consumption of animal products. For example, Mercy for Animals’ investigation of a dairy farm connected to DiGiorno Pizza, owned by Nestle, provoked such a media and public response that Nestle decided to work with MFA to implement an animal welfare policy. Potential weaknesses include the possibility of making animal abuse on farms appear to be the result of a few anomalous offenders, rather than a systematic problem. There is also concern about diminishing marginal returns in media attention; MFA capped its number of investigations released in 2015 for this reason and is working to expand to other countries where saturation is less of a concern. ACE considers the weaknesses of undercover investigations to be limited (ACE n.d.h).
4.6 Corporate Outreach
Corporate outreach is a major avenue for pursuing large-scale improvements for animals. An early example is Henry Spira’s 1980 campaign to end the use of the Draize test on rabbits by the major cosmetics company Revlon, which resulted in Revlon and several other corporations funding research on alternatives to animal testing (Spira 1985). More recently, corporate outreach efforts by Mercy for Animals, The Humane League, The Humane Society of the United States, and other animal activist organizations have led many major American egg suppliers and purchasers (including Kraft-Heinz, McDonald’s, and Walmart) to adopt a cage-free egg policy (or commit to adopting one in the future; Charles 2016; Kell 2016).
ACE (n.d.i) suggests that carefully considered corporate outreach has high potential to reduce animal suffering in the short and mid-term, and recommend corporate outreach when conducted by an experienced, effective team. They list the merits of corporate outreach as bringing about immediate, clear change in animal welfare, changing industry norms, and the possibility of increasing the costs of raising animals and therefore eventually reducing the number of animals raised in factory farms. Downsides to corporate outreach, according to ACE, include its dependency on what corporations and the public already view as excessively cruel (and therefore the changes they are willing to tolerate). ACE also acknowledges the concern that such reforms might strengthen animal agriculture in the long term by making the public more comfortable with the conditions in which farm animals are raised. However, ACE (n.d.i) concludes that the long-term consequences of this intervention are more likely to be positive than negative, given the importance of promoting concern for animals’ interests and the absence of strong evidence of negative effects.
One concerning aspect of voluntary policy change is that such policies are more likely to be reversed than legal reforms. Austrian animal rights leader Martin Balluch cites this drawback in arguing that political reform should be the priority of animal rights activists, pointing to Austrian clothes company Kleider Bauer’s reversal of its no-fur policy (Balluch 2005).
4.7 Legal Change
4.7.1 Legal Personhood
Lawyer Steven Wise has highlighted animals’ status as legal property as a major obstacle to improving their treatment (Wise 2000). Wise is director of the Nonhuman Rights Project, which is currently pursuing legal personhood for animals in the United States by working to obtain writs of habeas corpus on behalf of captive chimpanzees and elephants (Westoll 2016). Sentience Politics has launched a popular initiative in Basel, Switzerland to secure fundamental rights for non-human primates, which it regards as a foot-in-the-door to rights for other animals, including those raised on factory farms (Sentience Politics n.d.c).
ACE states that they are highly uncertain about whether direct efforts to secure non-human rights are more cost-effective than spreading anti-speciesist values in order to create a social climate in which the extension of rights to non-humans is more likely. ACE proposes studying whether progress in public opinion the context of other social movements has fallen backwards due to a lack of legal reform; whether legal change in other social movements has reversed due to lack of concomitant change in public opinion; the extent to which legal work gains media attention and shifts public opinion; and whether judges make decisions more aligned with public opinion in more heavily publicised cases (Reese 2016).
4.7.2 Legislative / Ballot Reforms
The effectiveness of legislative or ballot reforms, such as California’s 2008 Proposition 2 to increase the space requirements for farmed animals, has not been rigorously compared to other methods of activism. However, none of ACE’s current top charities (Animal Equality, Mercy for Animals, and The Humane League) invests a large percentage of its budget in legislative or ballot-initiative campaigns (ACE 2014a; ACE 2014b; ACE 2014c), suggesting that effectiveness-minded animal activist organizations have determined these campaigns are not the most effective activities on the margin.
4.8 Other Interventions
Other interventions used by animal advocates on behalf of animals include publicly advertising vegan or animal protection messages; open rescue, in which farm animals are rescued from farms while rescuers document the farm conditions (e.g. Liebman 2004); and protests, including street protests (e.g. Munro 2005) and disruption of public animal product consumption (such as those carried out by activist group DxE). The effectiveness of these and other tactics have not been rigorously studied by effective animal advocates, though ACE has an ongoing Social Movements Project attempting to identify successful strategies from other social movements which may be transferrable to animal protection (Smith 2015), and DxE lead organizer Wayne Hsiung cites a number of social scientific and historical sources in arguing for the effectiveness of DxE’s confrontational activism (Hsiung 2014).
4.9 Comparing Interventions Across Countries
Little research has been undertaken on how the country or region in which an intervention takes place influences its effectiveness. ACE lists the considerations it would use to make country prioritization decisions as importance/scale (the amount of animal suffering in the country), tractability (the ease with which progress could be made in the country), neglectedness (the amount of actors already working on problems in the country), and influence (the extent to which progress in the country influences progress elsewhere; ACE n.d.j).
- Animal Product Alternatives
Animal product alternatives fall into two categories: cellular agriculture, the production of animal products from cell or tissue cultures instead of animals, and plant-based food technology, the production of realistic animal product analogues entirely from plants. The development of cost-competitive animal product alternatives may be among the most effective methods of reducing animal suffering, given its potential to replace factory farming without relying on policy reform or major ethically-motivated lifestyle changes.
5.1 Cellular Agriculture
Cultured meat was predicted in 1930 (Smith 1930), and there were reports of culturing mammalian tissue as early as 1910 (Witkowski 1980). Today, cultured meat involves either cell culture (scaffold-based) or tissue culture/tissue engineering (self-organising) techniques (Edelman et al., 2005). Cellular agriculture startups Perfect Day Foods and Clara Foods are using yeast cultures to develop cultured dairy and egg whites, respectively.
Notable individuals and organisations working in cellular agriculture include Mark Post (University of Maastricht researcher working on cultured beef; Datar 2015), Paul Mozdziak (North Carolina State University Researcher working on cultured chicken), Memphis Meats (cultured meat company), Perfect Day Foods (cultured dairy company; originally Muufri), SuperMeat (cellular meat startup) and the Modern Agriculture Foundation (non-profit promoting cultured meat development) in Israel, New Harvest (non-profit promoting cellular agriculture development), and Clara Foods (cultured egg white company). As of 2016, there are an estimated five researchers working primarily on cellular agriculture, with 50-100 interested researchers in related fields (Rorheim et al., 2016).
Rorheim et al. (2016) provides a high level summary of cellular agriculture. The authors argue for increased support for cultured meat development and research, which includes (in order of priority); “research and development of technology suitable for mass production”, “promoting fact-based public discussion regarding the technology and its societal implications”, and “eventual marketing of end products to consumers.”
Rorheim et al. (2016) report that cellular agriculture currently lacks adequate funding and talent, which makes donating to or working for a cellular agriculture research institute or company a promising avenue for effective animal advocacy. However, despite the lack of researchers working directly on cellular agriculture, some technological barriers faced by cellular agriculture are also faced by other, less neglected fields in biology (e.g. tissue engineering; OPP 2015).
The availability of cost-competitive cultured animal products would allow consumers to abandon factory farmed or wild-caught animal foods while maintaining omnivorous diets at little or no cost, thereby driving potentially substantial reductions in factory farming and commercial fishing. In addition to these demand-driven effects, the ability to consume cruelty-free animal products may reduce the cognitive dissonance people have about supporting animal rights and anti-speciesism, thereby spurring reforms on behalf of animals (Rorheim et al., 2016).
Perhaps the most serious concern over cellular agriculture as a path to reducing animal suffering is whether cost-competitive cultured animal products can be developed at all. The Open Philanthropy Project (OPP 2015) suggest that the development of cost-competitive cultured meat poses a major challenge, and have been unable to find any concrete paths likely to achieve that goal. OPP draw this conclusion based on interviews with cellular agriculture researchers and the failure of similar projects (tissue engineering company Organogenesis and synthetic biofuel company Amyris) to achieve mass-market costs. Workers in the field have offered a number of conflicting projections as to the arrival time and cost of cultured animal products, suggesting a fair degree of uncertainty about the technology’s prospects (OPP 2015; Madrigal 2013).
A second concern is the degree to which consumers will switch to cost-competitive animal products if they do become available. A survey conducted in 2012 by YouGov of 1729 adults in Great Britain found that only 20% of non-vegetarian/vegan adults say they would eat in vitro meat if it were commercially available (YouGov 2012), though younger generations do appear to be more willing to try it (Griggs 2014). Other surveys show similar results (e.g. Smith 2014; De Boo 2013), though in more recent polls around 70% of respondents said they would like to try cultured meat when it is available (Rorheim et al., 2016). However, it is not clear how well opinion polls taken during the early development of a novel technology predict eventual acceptance.
Other evidence for potential barriers to uptake includes arguably irrational opposition to other technologies, such as GMOs and vaccines. It is also possible that a significant segment of the population will simply be indifferent between typical and cultured animal products. Despite these possible limitations, even a small minority of omnivores switching to cultured animal products could result in major reductions in animal suffering. This is especially true if cultured animal products can be made superior in cost, quality, and/or safety.
5.2 Plant-based Food Technology
While plant-based animal product analogues such as plant milk and veggie burgers have existed for decades, we focus on efforts to develop plant-based foods highly similar to animal products, which have emerged fairly recently. The main organisations currently working in the plant-based food technology industry include Impossible Foods, Beyond Meat (both of which develop plant-based meat substitutes), and Hampton Creek (which develops plant-based mixes, dressings, cookies, mayos and cookie dough). Impossible Foods introduced its ground beef substitute in 2016, which uses synthetic heme to replicate some characteristics of traditional meat. As of August 2016, Beyond Meat products are available in four American states, and some are being stocked in meat departments as a way to attract meat-eaters.
Plant-based food technology products are already commercially available, and some are approximately comparable in cost to the animal product equivalents. As with cultured animal products, plant-based animal product alternatives have the advantage that they may allow significant reductions in animal product consumption without requiring consumers to make drastic changes in their diet. Plant-based food technology may suffer less than cultured animal products from concerns over “unnaturalness”.
The appeal of plant-based food technology is likely to be limited by its inability to create foods identical to typical animal products, as is theoretically possible with cellular agriculture. Even if the taste and texture of plant-based foods are indistinguishable from animal products, consumers may still not choose the plant-based versions.
- Wild-Animal Suffering
Given the vast number of wild animals, and strong reasons to believe that a large fraction of these animals suffer considerably (Ng 1995), some effective animal advocates are concerned with finding ways to reduce suffering in the wild.
In one of the earliest academic treatments of wild-animal suffering, Ng (1995) proposed the field of welfare biology, the study of biology and ecology with the goal of improving the lives of individual animals (as opposed to conservation biology, which seeks to understand nature to better conserve species, ecosystems, natural resources, etc. for human use or for their intrinsic value).
Ng (1995) argues that most wild animals may have lives not worth living, due to the fact that the overwhelming majority of wild animals are r-selected. R-selected species produce many offspring, of which only a few survive to adulthood; the rest are eaten, starve to death, die from disease, or are killed some other way. This means that most wild animals die painful deaths after a short life, leading Tomasik (2015c) to the counterintuitive conclusion that an effective means of helping animals may be reducing the amount of wilderness. As discussed above, these considerations complicate the case for the effectiveness of veg*n outreach, whose effects on wild animals via impacts on climate change, land-use changes, and attitudes toward wild-animal suffering are highly unclear.
Considering the long-term effects of interventions to reduce animal suffering is critical, as most of the impact of today’s actions probably lies in the far future (Beckstead 2013). Tomasik (2015c) argues that one of the best ways for the animal-advocacy movement to reduce wild-animal suffering is to promote general concern for wild animals now in the hopes that future populations will be more motivated to help wild animals, and more informed as to the most effective interventions. It is difficult to make quantitative estimates of cost-effectiveness for values-spreading (promoting concern for some issue), but it potentially has a much greater impact in the long run than more direct interventions, as it can impact the actions of individuals in the future due to flow-through effects. Tomasik (2015c) also argues that animal advocates should not oppose all forms of human intervention in the lives of animals, as this may preclude future generations from humanitarian intervention on behalf of wild animals. Ng (1995) makes a similar point that the total abolition of animal testing may be bad for animal welfare in the long run, as scientific advances may be used to reduce the amount of suffering in wild animal populations.
Tomasik (2007) also suggests the development of humane insecticides as a highly effective intervention, given that trillions of insects suffer possibly highly painful deaths from conventional insecticides. While it is unclear whether insects are conscious, according to Tomasik, assigning even a small probability to insect consciousness implies a large expected value of helping them, given their massive numbers. Sentience Politics’ position paper (Sentience Politics n.d.b) on invertebrate suffering provides an overview of the evidence for pain in invertebrates and related considerations.
More speculative interventions on behalf of wild animals include Pearce’s proposals to reduce predator populations or alter their genomes to reduce predation (Pearce 2009), and that of “cosmic rescue missions”, in which future space-faring civilizations intervene on behalf of wild animals living on other planets (Pearce 1995).
Tomasik (B. Tomasik pers. comms. 2016) has suggested the following areas as being critical for further research for wild-animal suffering:
- What is the net impact of climate change, geoengineering, crop cultivation, cattle grazing, overfishing, eutrophication, and other large-scale changes on wild-animal suffering?
- What are the driving forces of the significant declines in vertebrate and invertebrate populations (Dirzo et al., 2014)?
- What are the implications of total invertebrate biomass being greater in certain land types than others (Tomasik 2016)?
- What is the quality of life of common wild animals and insects?
- Meta-research on the strategy of reducing wild-animal suffering, e.g. movement growth and policy change.
- What actions can be taken now to minimise wild- animal suffering in the far future?
- What effect do animal rights and veganism promotion have on views about environmentalism and wildlife preservation?
- How effective and safe are interventions to reduce wild-animal suffering (e.g. Tomasik 2013b)?
Two special issues of Relations. Beyond Anthropocentrism contain a number of papers on the problem of wild-animal suffering. The editorial paper (Faria and Paez 2015) summarises each of these papers and is recommended for further reading. Horta (2010) addresses criticisms of ethical concern for wild-animal suffering.
Thus far we have discussed methods of effective animal advocacy which have relatively direct impacts on animals or their consumers. Another approach is meta-strategy, such as building the effective animal advocacy movement, encouraging individuals to give a percentage of their income to effective animal causes and creating giving norms, prioritisation research, and increasing the effectiveness of the movement. ACE and Sentience Politics are the main organizations working in meta-strategy.
The meta-strategy approach to effectively helping animals is relatively new, and has been the subject of little research. However, given the multiplier effects of activities such as bringing more money and talent into the movement, identifying the most effective interventions and increasing the effectiveness of existing intervention, meta-strategy is a candidate for the most effective use of marginal animal advocacy resources. Building the Effective Altruism movement generally may also be highly effective given that effective animal advocacy is a major Effective Altruist focus area. For further reading on prioritisation research and movement building, see Sentience Politics (n.d.d) and Cotton-Barratt (2015).
In this paper, we have discussed a number of the interventions proposed for reducing the suffering of animals, particularly those used for food, through welfare reform or creating new vegans, vegetarians and meat reducers. We have also discussed a number of related fields, such as the psychology of meat eating and diet change, and the technology of cellular agriculture. We have also reviewed research and possible interventions related to wild-animal suffering, a topic which appears neglected given its scale.
Throughout the paper, we have suggested a number of research questions that either represent major gaps in the literature or are opportunities to have a high impact based on a combination of other research and our own recommendations. We urge future research in the field of animal advocacy and reducing animal suffering to focus on these areas.
In light of the above considerations, tentative conclusions about the most promising avenues for effectively reducing animal suffering may be made. ACE suggests corporate outreach and undercover investigations as two of the most effective interventions on behalf of farm animals. Work in cellular agriculture and plant-based food technology may also be an extremely high-impact approach to helping farmed animals, given these developments’ potential to replace animal agriculture while bypassing the enormous psychological and political hurdles currently in place, as well as their lack of funding and talent (at least in the case of cellular agriculture). Sentience Politics argues that meta-strategies such as movement-building and values-spreading are vastly underrated, and is currently campaigning for fundamental rights for primates on the grounds that this may make victories for larger groups of animals easier in the future. Others contend that wild-animal suffering should be a higher priority due to its neglectedness and massive scale, proposing more research on this problem, as well as possible interventions (e.g. humane insecticides) and general values-spreading.
i “Veganism” refers to the avoidance of all products of animal use (in food, clothing, cosmetics, etc.) insofar as is practicable. However, since the consumption of animal food products accounts for the great majority of human animal use and is the focus of much effective animal activism, we are concerned mainly with a vegan diet.
ii ACE does not believe that online ads cause no reduction in dairy and egg consumption; these estimated zeros are due to measuring dietary change in “vegetarian-equivalents”.
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