Are humans evolved specialists for running in the heat? Man vs. horse races provide empirical insights

Abstract

Many mammals run faster and for longer than humans and have superior cardiovascular physiologies. Yet humans are considered by some scholars to be excellent endurance runners at high ambient temperatures, and in our past to have been persistence hunters capable of running down fleeter quarry over extended periods during the heat of the day. This suggests that human endurance running is less affected by high ambient temperatures than is that of other cursorial ungulates. However, there are no investigations of this hypothesis. We took advantage of longitudinal race results available for three annual events that pit human athletes directly against a hyperadapted ungulate racer, the thoroughbred horse. Regressing running speed against ambient temperature shows race speed deteriorating with hotter temperatures more slowly in humans than in horses. This is the first direct evidence that human running is less inhibited by high ambient temperatures than that of another endurance species, supporting the argument that we are indeed adapted for high temperature endurance running. Nonetheless, it is far from clear that this capacity is explained by an endurance hunting past because in absolute terms humans are slower than horses and indeed many other ungulate species. While some human populations have persistence hunted (and on occasion still do), the success of this unlikely foraging strategy may be best explained by the application of another adaption-high cognitive capacity. With dedication, experience and discipline, capitalising on their small endurance advantage in high temperatures, humans have a chance of running a more athletic prey to exhaustion. K E Y W O R D S evolution, persistence hunting, temperature 1 INTRODUCTION 'Humans are the sole species of mammal that excels at long distance trekking and running in extremely hot conditions' (Lieberman, 2015). This claim is the culmination of arguments put forward by a number of authors including Bramble and Lieberman (2004), Carrier (1984) and This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Pace setting as an adaptive precursor of rhythmic musicality

“…53,54 Specific adaptive features (which we possess in contrast to living primate relatives and hominins prior to H. erectus) include the Achilles tendon, foot arch, expanded joint surfaces to absorb shock, hip and shoulder adaptations to increase torque, reduced forearm mass, and many features related to heat dissipation, including increased number and elaboration of sweat glands, less body hair, ability to mouth breathe, and so on. 50,[55][56][57] Furthermore, although not particularly effective sprinters, we are, uniquely among primates, good endurance runners. Several genetic and developmental traits are specifically associated with endurance running capabilities, and many of the thermoregulatory and other adaptations we exhibit are particularly enabling for endurance running.…”

Quantitative biological data in Pliny’s Naturalis Historia: a comparison of records of human strength, size and endurance in the classic Roman books, with modern Olympic records

“…For extremes of the human powers, he cites Crates of Pergamus for the statement that the Troglodytae of Africa are able to outrun a horse, an apparently fantastical statement that recently has been shown to be real under appropriate circumstances (Halsey & Bryce, 2020).…”

“…He also mentions the Panotti, with ears so large that they cover the whole body ( Figure 6). There is no reported malformation that results in gigantic ears (Halsey & Bryce, 2020), so this story is more probably based on an exaggerated report on artificially enlarged ears, like those of Ethiopia, which took place in the time of the Romans and could have been known to them thanks to geographic proximity to the empire (LaTosky, 2014). One of the most fantastical statements reproduced by Pliny describes a tribe without necks, and with eyes in their shoulders (Figure 7).…”

An introduction to the Special Issue on “Sports Science: Evolutionary Perspectives and Biological Mechanisms”

“…For example, there may have been selective pressures leading to the evolution of athletic performance in the context of the physical or ecological environment (for example, for adapting to hot vs. cold climatic conditions), or in the context of foraging behavior, or both (selection for foraging in hot climate conditions). Even if humans may not be an elite endurance species compared to cursory mammals (Halsey and Bryce, 2021), our ability to perform endurance activities during hot periods of the day, along with a set of peculiar traits such as bipedal locomotion, running ability (we are the only primate species with this ability) (Bramble 1 3 & Lieberman, 2004), hairlessness, eccrine sweat glands (Best & Kamilar, 2018) and regulation of water balance (Pontzer et al, 2021) beg for an evolutionary explanation (Liebenberg, 2006;Lieberman & Bramble, 2007;Lieberman, 2012).…”