Who we study:

Red-footed booby

Sula sula, pantropical distribution. This is a fairly pelagic species. They feed mostly on flying fish and some squid, and are the only species of booby that nests in trees. They have bright red feet, teal facial skin that melds into a red and periwinkle bill, and exist in two plumage morphs: brown and white.

Brown booby

Sula leucogaster, pantropical distribution. This species feeds on both flying fish and squid, and builds nests on the ground with broken shells, rocks, and, unfortunately plastic and other junk. They have yellow feet, and the color of their facial skin through their beak blends from a teal green to a yellow, with considerable variation. They also exist in two plumage morphs: the morph displayed here is typical of both sexes globally, but males in the eastern Pacific have light gray to white heads.

photo by Danilo da Castro - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=32848909

Masked booby

Sula dactylatra, pantropical distribution. Eats mostly flying fish and squid, and takes the longest foraging trips of any booby, excluding the Nazca booby. Has deep blue-black facial skin, a pale yellow bill, and variable foot coloration, from orange to grey to khaki to sometimes a grey/purplish color.

Photo by Stefan Hunt - Imported from 500px (archived version) by the Archive Team. (detail page), CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=78766521

Nazca booby

Sula granti, Galapagos endemic. Easily confused with the masked booby, from which it was only recently taxonomically split due to evidence of mitochondrial divergence (Friesen et al. 2002) and morphological and ecological differences (Pitman and Jehl 1998). The most distinctive feature is its orange bill.

Peruvian booby

Sula variegata is an endemic species of the Humboldt Current and ranges from islands off the northern coast of Peru down to central Chile. Eats mostly Peruvian anchovies. Their feet are a faded grey periwinkle, their facial skin black, their bills a faded cold grey, their eyes a deep red, and their plumage speckled brown on the wings, back, and tail, and white elsewhere.

Blue-footed booby

Sula nebouxii, ranges from the Gulf of California down to islands off the northern coast of Peru. Eats mostly anchovies, sardines, and some squid and flying fish. Their bright blue feet have been shown to vary in color within the same individual, and that color variation affects the investment of their mates in caretaking for their chicks.

What we study:

We are analyzing several whole genome sequences of each species. We intend to confirm the hypothesized phylogenetic relationships, identify regions of the genome that are under positive selection, as well as highly differentiated regions, and explore the gene ontology terms associated with these regions. We will also be looking for patterns of incomplete lineage sorting between these species, several of which are known to hybridize. From this, we hope to hypothesize as to which genes are of evolutionary importance to some of these species, and to design field and lab experiments to further explore these differences.

This represents an expansion of Scott’s dissertation work studying population genetics and hybridization between blue-footed and Peruvian boobies.



Taylor SA, Morris-Pocock JA, Tershy BR, Castillo-Guerrero JA, Friesen, VL. 2013. Genetic evidence for hybridization between brown (Sula leucogaster) and blue-footed (S. nebouxii) boobies in the Gulf of Mexico. Marine Ornithology 41: 113 - 119.  PDF

Taylor SA, Anderson DJ, Friesen VL. 2013. Evidence for asymmetrical gene flow of nuclear loci, but not mitochondrial loci, between a seabird species pair. PLoS ONE. 8(4): e62256.  PDF


Taylor SA, Friesen VL. 2012. Evidence for strong assortative mating, limited gene flow, and strong differentiation across the blue-footed / Peruvian booby hybrid zone in northern Peru. Journal of Avian Biology 43: 311-324.  PDF

Taylor SA, Friesen V L. 2012. Potential uses of molecular genetics for understanding seabird evolution, ecology and conservation. Marine Ecology Progress Series. 451: 285-304.  PDF


Taylor SA, Zavalaga CB, Luna –Jorquera G, Simeone A, Anderson DJ, Friesen VL. 2011. Panmixia and high genetic diversity in a Humboldt Current endemic, the Peruvian Booby (Sula variegata). Journal of Ornithology. 152: 623-630.  PDF

Taylor SA, *Maclagan L, Anderson DJ, Friesen VL. 2011. Could specialization to cold water upwelling systems influence genetic diversity and gene flow in marine organisms? A case study using the blue-footed booby, Sula nebouxii. Journal of Biogeography. 38: 883-893. *Undergraduate honors student  PDF


Taylor SA, Zavalaga CB, Friesen VL. 2010. Hybridization between blue-footed (Sula nebouxii) and Peruvian (S. variegata) boobies in northern Peru. Waterbirds 33: 251-257.  PDF

Zavalaga CB, Halls JN, Mori GP, Taylor SA, Dell’Omo G. 2010. At-sea movement patterns and diving behavior of Peruvian boobies Sula variegata : sexual segregation by foraging habitat in a rich marine environment? Marine Ornithological Progress Series 404: 259-274.  PDF

Morris-Pocock JA, Taylor SA, Birt T, Friesen VL. 2010. Concerted evolution of duplicated mitochondrial control regions in three related seabird species. BMC Evolutionary Biology 10: 14.  PDF

Morris-Pocock J A, Taylor SA, Sun Z, Friesen VL. 2010. Isolation and characterization of 15 microsatellite loci for red-footed (Sula sula), blue-footed (S. nebouxii) and Peruvian (S. variegata) boobies. Molecular Ecology Resources 10: 404-408. 

Taylor SA, Morris-Pocock JA, Sun Z, Friesen VL. 2010. Isolation and characterization of 10 microsatellite loci in blue-footed (Sula nebouxii) and Peruvian boobies (Sula variegata). Journal of Ornithology 151: 525-528.  PDF


Zavalaga CB, Taylor SA, Dell’Omo G, Anderson DJ, Friesen VL. 2009. Male/female classification of the Peruvian booby. Wilson Journal of Ornithology 121: 739-744.  PDF