The Jean Shepherd story "Scut Farkas and the Murderous Mariah" revolves around top-spinning in the fictional Depression-era American city of Hohman, Indiana. The bully and the named top in the title are challenged by Shepherd's ongoing protagonist Ralph and a so-called "gypsy top" of similar design to Mariah named Wolf. [10] The hummingbird evolutionary tree shows that one key evolutionary factor appears to have been an altered taste receptor that enabled hummingbirds to seek nectar. [48]

A spinning top, or simply a top, is a toy with a squat body and a sharp point at the bottom, designed to be spun on its vertical axis, balancing on the tip due to the gyroscopic effect. a b White, Richard (19 September 2015). "Hummingbird hawk moth, hummingbird and sunbird". Bird Ecology Study Group . Retrieved 8 March 2023.

Use and duration of torpor vary among hummingbird species and are affected by whether a dominant bird defends territory, with nonterritorial subordinate birds having longer periods of torpor. [129] A hummingbird with a higher fat percentage will be less likely to enter a state of torpor compared to one with less fat, as a bird can use the energy from its fat stores. [120] Torpor in hummingbirds appears to be unrelated to nighttime temperature, as it occurs across a wide temperature range, with energy savings of such deep sleep being more related to the photoperiod and duration of torpor. [120] Lifespan [ edit ] By merely shifting position, feather regions of a muted-looking bird can instantly become fiery red or vivid green. [68] In courtship displays for one example, males of the colorful Anna's hummingbird orient their bodies and feathers toward the sun to enhance the display value of iridescent plumage toward a female of interest. [69]

One study of Anna's hummingbirds found that dietary protein was an influential factor in feather color, as birds receiving more protein grew significantly more colorful crown feathers than those fed a low-protein diet. [70] Additionally, birds on a high-protein diet grew yellower (higher hue) green tail feathers than birds on a low-protein diet. [70] Specialized characteristics and metabolism [ edit ] Humming [ edit ] A calliope hummingbird hovering near a feeder, creating the "humming" sound from its rapid wingbeats, while chirping by vocalization In Sonic Advance 3, the Hop Jump returned as Sonic and Amy's Long Wind Jump maneuver, and one of their Special Actions. [2] [3] Here, Sonic's Humming Top look like it did in Sonic Advance 2, except its winds are white instead of blue. Amy's is visually unchanged.The quality materials and manufacture of the Humming top add to the traditional appeal, whilst the fresh and contemporary styles will be a hit with young children. While hovering, hummingbirds do not benefit from the heat loss by air convection during forward flight, except for air movement generated by their rapid wing-beat, possibly aiding convective heat loss from the extended feet. [104] [107] Smaller hummingbird species, such as the calliope, appear to adapt their relatively higher surface-to-volume ratio to improve convective cooling from air movement by the wings. [104] When air temperatures rise above 36°C (97°F), thermal gradients driving heat passively by convective dissipation from around the eyes, shoulders, and feet are reduced or eliminated, requiring heat dissipation mainly by evaporation and exhalation. [104] In cold climates, hummingbirds retract their feet into breast feathers to eliminate skin exposure and minimize heat dissipation. [107] Kidney function [ edit ] Bleiweiss, R.; Kirsch, J.A.; Matheus, J.C. (1997). "DNA hybridization evidence for the principal lineages of hummingbirds (Aves:Trochilidae)". Molecular Biology and Evolution. 14 (3): 325–343. doi: 10.1093/oxfordjournals.molbev.a025767. PMID 9066799. a b c d e f g h i "What is a hummingbird?". Smithsonian’s National Zoo and Conservation Biology Institute. 2023 . Retrieved 7 March 2023. As calculated by displacement of body size, the rufous hummingbird makes perhaps the longest migratory journey of any bird in the world. At just over 3 inches (7.6cm) long, rufous hummingbirds travel 3,900 miles (6,300km) one-way from Alaska to Mexico in late summer, a distance equal to 78,470,000 body lengths, then make the return journey in the following spring. [167] [171] By comparison, the 13 inches (33cm)-long Arctic tern makes a one-way flight of about 11,185 miles (18,001km), or 51,430,000 body lengths, just 65% of the body displacement during migration by rufous hummingbirds. [171]

Hummingbird kidneys also have a unique ability to control the levels of electrolytes after consuming nectars with high amounts of sodium and chloride or none, indicating that kidney and glomerular structures must be highly specialized for variations in nectar mineral quality. [111] Morphological studies on Anna's hummingbird kidneys showed adaptations of high capillary density in close proximity to nephrons, allowing for precise regulation of water and electrolytes. [110] [112] Hemoglobin adaptation to altitude [ edit ] Alternatively, tops of this class may be started by hand but then accelerated and kept in motion by striking them repeatedly with a small whip. Hummingbirds are highly sensitive to stimuli in their visual fields, responding to even minimal motion in any direction by reorienting themselves in midflight. [77] [78] [80] Their visual sensitivity allows them to precisely hover in place while in complex and dynamic natural environments, [80] functions enabled by the lentiform nucleus which is tuned to fast-pattern velocities, enabling highly-tuned control and collision avoidance during forward flight. [77] Song, vocal learning, and hearing [ edit ] Complex songs of male wedge-tailed sabrewing hummingbirds ( Campylopterus curvipennis) in mating leks of eastern Mexico [81] Hummingbirds split from their sister group, the swifts and treeswifts, around 42 million years ago. [8] The oldest known fossil hummingbird is Eurotrochilus, from the Rupelian Stage of Early Oligocene Europe. [9] Description [ edit ] Size of Mellisuga helenae (bee hummingbird) – the world's smallest bird – compared to a human hand Adult male bee hummingbird, Cuba Chaos Emerald | Item Box ( 1UP, 5 Ring Bonus, Attract, Barrier, Boost Up, Confusion, High Speed, Invincible, Magnetic Barrier, Maximum Tension Bonus, Random Ring Bonus, Repair, Score Bonus, Slow, Tension Bonus, Tension Bonus (multiplayer)) | Medal | Sol Emerald | Switch | Ring | Snowboard | Treasure chestThe highest recorded wingbeats for wild hummingbirds during hovering is 88 per second, as measured for the purple-throated woodstar ( Calliphlox mitchellii) weighing 3.2g. [155] The number of beats per second increases above "normal" while hovering during courtship displays (up to 90 per second for the calliope hummingbird, Selasphorus calliope), a wingbeat rate 40% higher than its typical hovering rate. [156] Some modern tops are kept perpetually in motion by spinning magnetic fields from a special ground plate. Baldwin, M.W.; Toda, Y.; Nakagita, T.; O'Connell, M.J.; Klasing, K.C.; Misaka, T.; Edwards, S.V.; Liberles, S. D. (2014). "Evolution of sweet taste perception in hummingbirds by transformation of the ancestral umami receptor". Science. 345 (6199): 929–933. Bibcode: 2014Sci...345..929B. doi: 10.1126/science.1255097. PMC 4302410. PMID 25146290. During evolution, hummingbirds adapted to the navigational needs of visual processing while in rapid flight or hovering by development of the exceptionally dense array of retinal neurons, allowing for increased spatial resolution in the lateral and frontal visual fields. [75] Morphological studies of the hummingbird brain showed that neuronal hypertrophy – relatively the largest in any bird – exists in a region called the pretectal nucleus lentiformis mesencephali (called the nucleus of the optic tract in mammals) responsible for refining dynamic visual processing while hovering and during rapid flight. [76] [77]

Harman, Peter Michael (1998). The Natural Philosophy of James Clerk Maxwell. Cambridge University Press. ISBN 0-521-00585-X. Another evolutionary cause of this sexual bill dimorphism is that the selective forces from competition for nectar between the sexes of each species drives sexual dimorphism. [65] Depending on which sex holds territory in the species, the other sex having a longer bill and being able to feed on a wide variety of flowers is advantageous, decreasing intraspecific competition. [66] For example, in species of hummingbirds where males have longer bills, males do not hold a specific territory and have a lek mating system. [66] In species where males have shorter bills than females, males defend their resources, so females benefit from a longer bill to feed from a broader range of flowers. [66] Feather colors [ edit ] Male Anna's hummingbird showing iridescent crown and gorget feathersTails | Marine | Coconut Crew ( Colonel, Daikun, Gardon, Kylok, Muzy, Setter, Tabby) | Norman | Captain Whisker | Mini & Mum | Johnny | Eggman | Eggman Nega Prinzinger, R.; Schafer, T.; Schuchmann, K.L. (1992). "Energy metabolism, respiratory quotient and breathing parameters in two convergent small bird species: the fork-tailed sunbird Aethopyga christinae (Nectariniidae) and the chilean hummingbird Sephanoides sephanoides (Trochilidae)". Journal of Thermal Biology. 17 (2): 71–79. doi: 10.1016/0306-4565(92)90001-V. The wingbeats causing the hum of hummingbirds during hovering are achieved by elastic recoil of wing strokes produced by the main flight muscles: the pectoralis major (the main downstroke muscle) and supracoracoideus (the main upstroke muscle). [73] Vision [ edit ] Male rufous hummingbird ( Selasphorus rufus) displaying a proportionally large eye in relation to its head