females are paler and occasionally a white-brown or yellow-white color. Other variations include a redder or yellower pigment with the occasional purple-brown color. Both males and females can have a brownish-gray border circling the edge of the wing. This border varies in thickness and appears to be more common in males than in females. The forewing can have a prominent or faint dark spot or, sometimes, no spot at all near the wing tip. The hindwings may also have eyespots or white dots. A white band runs along the underside of the wing and varies in width and fullness. Female small heath butterflies have a wingspan of 37 mm and tend to be larger than males, which have a wingspan of 33 mm. The small heath is diurnal, or is active in the daytime. It flies near the ground with a fluttering flight pattern. Small heaths are also lateral baskers, angling their bodies 90° to the sun with their wings closed when resting. Mating Aggression between males Male small heath butterflies often establish their own territories and become stationary. Males with their own territories are more likely to mate successfully with females. This prompts aggressive male behavior between stationary males and wandering males who may contest territory ownership. The stationary male sometimes engages the wandering male in an attempt to determine its sex, and these interactions remain short to reduce vulnerability to predation. Longer interactions between males are typically territorial disputes. Larger males are typically more successful in territorial disputes with other males, as they have longer wing spans and are superior in size and weight to smaller males. Thus, larger males have a significantly higher chance of successfully mating a female. Temperature plays a role in male-male interactions as well. Both females and males increase vagrancy with increased temperatures, and vice versa. In low-temperature conditions, it is advantageous for a male to remain stationary in order to defend his territory as a potential mating site. This leads to longer male-male interactions when territorial disputes are more likely to occur. However, when temperatures are high, choosing not to defend territory is the preferred and advantageous strategy in mating. This is because males who become vagrant will have a higher chance of intercepting a wandering female in competition with other vagrant males. This leads to shorter male-male interactions as males are not defending territory. Interactions between males and females Mate choice