Instruct: Given a question, retrieve relevant documents that answer the question.
Query: Who named the blue-footed booby?
The blue-footed booby was described by the French naturalist Alphonse Milne-Edwards in 1882 under the current binomial name Sula nebouxii.[6] The specific epithet was chosen to honor the surgeon, naturalist, and explorer Adolphe-Simon Neboux (1806-1844).[7] There are two recognized subspecies:[8]
The Peruvian boobies are thought to have a parapatric relationship with the blue-footed booby, and it is believed that their lineage diverged from 0.25-0.45 million years ago. Hybridization between the two species is far from unheard of; with hybrid females successfully able to lay eggs and raise resultant chicks. Hybridization occurs most frequently between female Peruvian boobies and male blue-footed boobies, while the inverse hybridization does still occur. It is speculated that this preference is a result of the more exaggerated sexual display of the male blue-footed booby, possibly causing him to seem a more captivating sexual partner than his Peruvian counterpart.
Isla de la Plata is a small island off the coast of Manabí, Ecuador, and is part of Parque Nacional Machalilla. It can be reached by boat from the city of Puerto López, which is 40 kilometers away.
On the island, there is a large diversity of animal species, including the blue-footed booby, red-footed booby, and the Nazca booby. Another species found here is the South American sea lion. 
The blue-footed booby (Sula nebouxii) is a marine bird native to subtropical and tropical regions of the eastern Pacific Ocean. It is one of six species of the genus Sula – known as boobies. It is easily recognizable by its distinctive bright blue feet, which is a sexually selected trait. Males display their feet in an elaborate mating ritual by lifting them up and down while strutting before the female. The female is slightly larger than the male and can measure up to 90cm (35in) long with a wingspan of up to 1.5m (5ft).[2]
In these three booby species, hatching order indicates chick hierarchy in the nest. The A-chick is dominant to the B-chick, which in turn is dominant to the C chick, etc. (when there are more than two chicks per brood) Masked booby and Nazca booby dominant A-chicks always begin pecking their younger sibling(s) as soon as they hatch; moreover, assuming it is healthy, the A-chick usually pecks its younger sibling to death or pushes it out of the nest scrape within the first two days that the junior chick is alive. Blue-footed booby A-chicks also express their dominance by pecking their younger sibling. However, unlike the obligately siblicidal masked and Nazca booby chicks, their behavior is not always lethal. A study by Lougheed and Anderson (1999) reveals that blue-footed booby senior chicks only kill their siblings in times of food shortage. Furthermore, even when junior chicks are killed, it does not happen immediately. According to Anderson, the average age of death of the junior chick in a masked booby brood is 1.8 days, while the average age of death of the junior chick in a blue-footed booby brood may be as high as 18 days. The difference in age of death in the junior chick in each booby species is indicative of the type of siblicide that the species practices. Facultatively siblicidal blue-footed booby A-chicks only kill their nest mate(s) when necessary. Obligately siblicidal masked and Nazca booby A-chicks kill their sibling no matter if resources are plentiful or not; in other words, siblicidal behavior occurs independently of environmental factors.
The blue color of the blue-footed booby's webbed feet comes from carotenoid pigments obtained from its diet of fresh fish. Carotenoids act as antioxidants and stimulants for the blue-footed booby's immune function, suggesting that carotenoid-pigmentation is an indicator of an individual's immunological state.[17] Blue feet also indicate the current health condition of a booby. Boobies that were experimentally food-deprived for forty-eight hours experienced a decrease in foot brightness due to a reduction in the amount of lipids and lipoproteins that are used to absorb and transport carotenoids. Thus, the feet are rapid and honest indicators of a booby's current level of nourishment.[17] As blue feet are signals that reliably indicate the immunological and health condition of a booby, coloration is favored through sexual selection.
The name booby comes from the Spanish word bobo ("stupid", "foolish", or "clown") because the blue-footed booby is, like other seabirds, clumsy on land.[3] They are also regarded as foolish for their apparent fearlessness of humans.[2]
The blue-footed booby is on average 81cm (32in) long and weighs 1.5kg (3.3lb), with the female being slightly larger than the male. Its wings are long and pointed and brown in color. The neck and head of the blue-footed booby are light brown with white streaks while the belly and underside exhibit pure white plumage.[12] Its eyes are placed on either side of its bill and oriented towards the front, enabling excellent binocular vision. Its eyes are a distinctive yellow, with the male having more yellow in its irises than the female. Blue-footed booby chicks have black beaks and feet and are clad in a layer of soft white down. The subspecies S. n. excisa that breeds on the Galápagos Islands is larger than the nominate subspecies and has lighter plumage especially around the neck and head.[9]
The blue-footed booby usually lays one to three eggs at a time. The species practices asynchronous hatching, in contrast to many other species whereby incubation begins when the last egg is laid and all chicks hatch together. This results in a growth inequality and size disparity between siblings, leading to facultative siblicide in times of food scarcity.[5] This makes the blue-footed booby an important model for studying parent–offspring conflict and sibling rivalry.
Blue-footed boobies make raucous or polysyllabic grunts or shouts and thin whistling noises. The males of the species have been known to throw up their head and whistle at a passing, flying female. Their ritual displays are also a form of communication.
The blue-footed booby is monogamous, although it has the potential to be bigamous.[16] It is an opportunistic breeder, with the breeding cycle occurring every 8 to 9 months.[22] The courtship of the blue-footed booby consists of the male flaunting his blue feet and dancing to impress the female. The male begins by showing his feet, strutting in front of the female. Then, he presents nest materials and finishes the mating ritual with a final display of his feet.[23] The dance also includes "sky-pointing", which involves the male pointing his head and bill up to the sky while keeping the wings and tail raised.[24]
Blue-footed boobies are less likely to commit siblicide and if they do, they commit it later after hatching than masked boobies. In a study, the chicks of blue-footed and masked boobies were switched to see if the rates of siblicide would be affected by the foster parents. It turns out that the masked boobies that were placed under the care of blue-footed booby parents committed siblicide less often than they would normally. Similarly, the blue-footed booby chicks placed with the masked booby parents committed siblicide more often than they normally did, indicating that parental intervention also affects the offspring's behavior.
Concerns of a decline in the booby population of the Galápagos Islands prompted a research project in its cause. The project, completed in April 2014, confirmed the population decline.[38] The blue-footed booby population appears to be having trouble breeding and thus is slowly declining. The decline is feared to be long-term, but annual data collection is needed for a firm conclusion that this is not a normal fluctuation.
The blue-footed booby is distributed among the continental coasts of the eastern Pacific Ocean from California to the Galápagos Islands down into Peru.[14] It is strictly a marine bird. Its only need for land is to breed and rear young, which it does along the rocky coasts of the eastern Pacific.[13]
The female blue-footed booby lays two or three eggs. Eggs are laid about four to five days apart. Both male and female take turns incubating the eggs, while the non-sitting bird keeps watch. Since the blue-footed booby does not have a brooding patch, it uses its feet to keep the eggs warm. The incubation period is 41–45 days. Usually, one to two chicks are hatched from the two to three eggs originally laid. The male and female share parental responsibilities. The male will provide food for the young in the first part of their life because of his specialized diving. The female will take over when the demand is higher.[10] Chicks feed off the regurgitated fish in the adult's mouth. If the parent blue-footed booby does not have enough food for all of the chicks, it will only feed the biggest chick, ensuring that at least one will survive.[5]
Like other sexually size-dimorphic birds, female blue-footed boobies usually favor the smaller sex during times of food scarcity. Booby chicks do not show clear differences in size based on sex, but females do grow faster than males, which means they require greater parental investment. Blue-footed boobies display behavior that is described in the Flexible Investment Hypothesis, which states that a female will adjust the allocation of resources to maximize her lifetime reproductive success. This was shown in an experiment in which females had their flight feathers trimmed, so that they had to expend more energy during flights to obtain food for their broods. Female chicks of such mothers were more strongly affected than their brothers, in that they had lower masses and shorter wing lengths.[25]
Red-footed booby pairs may remain together over several seasons. They perform elaborate greeting rituals, including harsh squawks and the male's display of his blue throat, also including short dances.
The Peruvian booby is within the genus "Sula". It shares this genus with other boobies, including the blue-footed booby, the red-footed booby, the brown booby, the masked booby, and the Nazca booby.
Food problems may be the cause of an observed failure of the birds to even try to breed. The results of the research suggest this is related to a decline in sardines (Sardinops sagax), an important part of the boobies’ diet. Earlier work on Española Island saw successful breeding in blue-footed boobies that have access to sardines, in which case their diet consists essentially wholly of sardines. However, sardines have been largely absent from the Española area since 1997, as has been shown from Nazca boobies there, who also prefer sardines but can breed using other prey. In 2012–13, roughly only half of prey items in the boobies' diet were sardines. No evidence was seen of other possible causes for the decline, such as effects of humans, introduced predators, or disease.[39]
There are no subspecies of Peruvian booby, but some members of the species have been seen to hybridize with blue-footed boobies.
Mates can recognize each other by their calls. Researchers have analyzed calls of blue-footed boobies and conducted playback experiments. Although calls differed between sexes, unique individual signatures were present. It was found that both males and females can discriminate the calls of their mates from others.[37]
Since the blue-footed booby preys on fish by diving headlong into the water, its nostrils are permanently closed, and it has to breathe through the corners of its mouth. Its most notable characteristic is its blue-colored feet, which can range in color from a pale turquoise to a deep aquamarine. Males and younger birds have lighter feet than females.[2] Its blue feet play a key role in courtship rituals and breeding, with the male visually displaying its feet to attract mates during the breeding season.
In one experiment, siblicide was shown to be somehow related to parental care. When non-obligate siblicidal blue-footed boobies were swapped with obligate siblicidal masked booby chicks, it was found that the blue-footed chicks exhibited more siblicidal behavior.
Compared to other species of boobies such as the blue-footed booby, siblicide is obligatory in the masked booby. One reason is because the masked boobies build very shallow flat nests, so older chicks can expel their younger siblings with relative ease. Blue-footed booby parents, meanwhile, build nests with steeper sides, thus preventing some older chicks from engaging in siblicidal behaviour.
Boobies are another group of seabirds known for their mating displays. Brown ("Sula leucogaster"), red-footed ("S. sula") and blue-footed boobies ("S. nebouxii") have at least nine described parts to their mating display. Sky pointing in boobies is similar to albatrosses; in the brown booby, sky pointing is described as a display where the male throws his head backwards, stretches his neck out, and usually gives a whistling vocalization. Parading is a well-known display in boobies as well; in this display, one individual in the pair - usually the male - walks upright, with his tail erect, swaying in an exaggerated manner from side to side while taking small steps. In blue-footed and red-footed boobies, parading also includes lifting and flaunting their brightly colored feet at their prospective partner.