Science & Technology

This Is Where Humans Rank on the Food Chain (Spoiler: We're Not on Top)

There's no denying the shared relentless ego that comes with being a human. Just look at us. Here we are, atop our thrones overlooking the animal kingdom, laughing at all the sad, helpless creatures beneath us on the food chain. One problem there: Our species definitely does not top the food chain. Oops.

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It's a Dog-Eat-Dog World

To know where an animal ranks on the food chain, ecologists calculate its trophic level. This ranking places different organisms in succession based on which organisms they eat, and/or are eaten by. For example, a minnow is lower on the scale than a shark. The number of steps an organism is from the start is a measure of its trophic level.

There are five trophic levels, and they look like this:


Level 2: Herbivores eat plants and are called primary consumers.

Level 3: Carnivores that eat herbivores are called secondary consumers.



Cruisin' for an Ego Bruisin'

Until 2013, no one had ever thought to apply this method to humans to see where we shake out. Maybe we all assumed we're top dogs? Or we were too scared to reveal the truth, perhaps? A French organization combined "ecological theory, demography, and socio-economics to calculate the human trophic level (HTL) and position humans in the context of the food web" and published their results in Proceedings of the Natural Academy of Sciences. By using food-supply data from the U.N Food and Agricultural Organization (FAO), the group calculated the HTL for the first time. The unflattering conclusion: Humans aren't all that superior.

According to the study, humans have a trophic level of about 2.21, based on our diet. On this 1-5 scale, a level one represents a primary producer (like a plant), and five represents a pure apex predator (a meat-eating animal with few or no predators, like a tiger, crocodile, or boa constrictor). Our halfway point on the food chain puts us in the company of anchovies and pigs.

The trophic level did vary slightly between regions, however. According to the research, Burundi had the lowest score at 2.04, due to a diet that was 96.7 percent plant-based. Iceland had the highest country score at 2.54, seeing as their diet consists of slightly more meats than plants. As a whole, the worldwide HTL has increased slightly over time, from about 2.15 in 1961 to 2.21 in 2013.

But this research does a bit more than knocking down the human ego a few notches. As the authors write, "HTL can be used by educators to illustrate the ecological position of humans in the food web, by policymakers to monitor the nutrition transition at global and national scales and to analyze the effects of development on dietary trends, and by resource managers to assess the impacts of human diets on resource use." You don't have to top the food chain to feel important, but we are getting a serious craving for steak right about now.


To learn about the apex predator in your own home, check out "The Lion in the Living Room: How House Cats Tamed Us and Took Over the World" by Abigail Tucker. We handpick reading recommendations we think you may like. If you choose to make a purchase, Curiosity will get a share of the sale.


Written by Joanie Faletto February 8, 2018
