Tail swish tsum simulator#

France responded by blockading the port of Algiers and led to the French rule of Algeria that lasted 132 years ( Rogan, 2012). The fly whisk even led Algeria into war in 1827, when the Dey of Algiers angrily struck the French ambassador three times with his fly whisk because France refused to pay their debts. In religions such as Buddhism or Jainism ( Beer, 2003 Williams, 2006), fly whisks ward off insects without killing them. In use for thousands of years ( Riegel, 1979), they eventually became a symbol of royalty ( Beer, 2003), or authority and power ( Riegel, 1979). They were made of the tail hair of yaks, oxen or horses ( Beer, 2003 Williams, 2006). Fly whisks, as shown in Fig. 1C,D, were designed to repel flies and other insects. Humans have designed a number of insect-repelling devices that mimic the mammal tail. Howler monkeys use up to 24% of their basal metabolism to slap their forearms to remove or deter insects ( Dudley and Milton, 1990).

All of these defensive actions require the expenditure of energy. Horses often stand next to one another head-to-tail or head-to-shoulder and swish their tails to protect the head and hindquarters of their neighbors ( Lefebvre et al., 2007). Ungulates stand in large groups to reduce the number of insect bites per individual by spreading the attacks among the crowd ( Mooring and Hart, 1992). Calves that defend themselves more are attacked by fewer stable flies than those who are less active ( Warnes and Finlayson, 1987). In fact, when biting insects are choosing a host, the primary selection factor is the type of defensive behavior exhibited ( Moore, 2002). Clearly, any behavior that prevents such flies from landing and biting will be beneficial to the host animal and be selected for in subsequent generations.ĭefensive behavior is a mammal's main repellant of insects ( Moore, 2002) and it has been long studied ( Harvey and Launchbaugh, 1982 Keiper and Berger, 1982 Waage and Nondo, 1982 Edman and Scott, 1987 Warnes and Finlayson, 1987 Toupin et al., 1996 Horváth et al., 2010). Bot flies are highly host-specific, ranging from mice to elephants ( Cowell et al., 2006), and can cause a reduction of mass gain of 20 to 27 kg per year in cattle ( Hart, 1990). Bot and warble flies deposit their eggs on the hairs of mammals and cause myiasis, the larval infestation of live vertebrates that eat the host's tissue. Stable flies alone are estimated to cost the US cattle industry $2.2 billion per year through reduced milk production and reduced mass gain ( Taylor et al., 2012). Up to 1000 flies per hour have been observed to land on horses ( Foil and Foil, 1988), and cows can lose 300 ml of blood per day owing to horse flies ( Tashiro and Schwardt, 1953). They can cause irritation, loss of blood, loss of resting and feeding time, disease infection and death ( Samuel et al., 2001 Mooring et al., 2007). This study may help us determine new mosquito-repelling strategies that do not depend on chemicals.īiting insects, such as mosquitoes ( Fig. 1B), black flies and horse flies, pose a significant threat to both domestic and wild mammals.

Tail swish tsum simulator#

The simulator generates mild breezes of 1 m s –1, comparable to a mosquito's flight speed, and sufficient to deter up to 50% of mosquitoes from landing. Based on our findings, we designed and built a mammal tail simulator to simulate the swinging of the tail. This whip-like effect requires substantial torques from the base of the tail on the order of 10 1–10 2 N m, comparable to the torque of a sedan, but still within the physical limits of the mammal. Tails can also be used like a whip to directly strike at insects. The tail swings at triple the frequency of a gravity-driven pendulum, and requires 27 times more power input. How effective is a mammal's tail at repelling insects? In this combined experimental and theoretical study, we filmed horses, zebras, elephants, giraffes and dogs swinging their tails. The swinging of a mammal's tail has long been thought to deter biting insects, which, in cows, can drain up to 0.3 liters of blood per day.