Scene From Above: Retinal Ganglion Cell Topography and Spatial Resolving Power in the Giraffe (Giraffa camelopardalis)
The giraffe (Giraffa camelopardalis) is a browser that uses its extensible tongue to selectively collect leaves during foraging. As the tallest extant terrestrial mammal, its elevated head height provides panoramic surveillance of the environment. These aspects of the giraffe’s ecology and phenotype suggest that vision is of prime importance. Using Nissl-stained retinal wholemounts and stereological […]
Scaling of the Appendicular Skeleton of the Giraffe (Giraffa camelopardalis)
Giraffes have remarkably long and slender limb bones, but it is unknown how they grow with regard to body mass, sex, and neck length. In this study, we measured the length, mediolateral (ML) diameter, craniocaudal (CC) diameter and circumference of the humerus, radius, metacarpus, femur, tibia, and metatarsus in 10 fetuses, 21 females, and 23 […]
Physiological cross-sectional area of the masticatory muscles in the giraffe (Giraffa camelopardalis)
Numerous studies have investigated how the skeletal morphology is related to feeding behaviour (Christiansen and Adolfssen 2005; Wroe et al. 2005; Christiansen and Wroe 2007; Ellis et al. 2009; Koyabu and Endo 2009; Koyabu et al. 2009; Koyabu and Endo 2010), although remarkably few studies have focused on the architecture of masticatory muscles from which […]
Observations on the giraffe central nervous system related to the corticospinal tract, motor cortex and spinal cord: what difference does a long neck make?
The mammalian corticospinal tract is known to contain axons that travel from the cerebral cortex to various levels of the spinal cord and its main function is thought to be the mediation of voluntary movement. The current study describes neuroanatomy related to the corticospinal tract of the giraffe. This animal presents a specific morphology that […]
The development of the reproductive organs of the male giraffe, Giraffa camelopardalis
The reproductive organs of the male giraffe differ little in morphology and histology from those of other ungulates. There is some indication that gonadal hypertrophy occurs in late fetal life. Spermatogenesis begins at 3-4years of age and coincides with a rapid increase of testicular weight and seminiferous tubule diameter. In the fetal testis the main […]
Development of the Giraffe Horn and Its Blood Supply
The giraffe horn is an unusual cranial exostosis that lacks clear delineation and categorization as either horn or antler. The distinction between the two is made by contrasting their methods of development and basic composition. This process of development has not been detailed in the giraffe, a factor contributing to the difficulty in distinguishing the […]
Anatomy of the Mouth of the Giraffe (Giraffa camelopardalis rothschildi)
The giraffe (Giraffa camelopardalis) is both the largest extant ruminant and a strict browser. We dissect and describe the macroscopic anatomy of the mouth of the giraffe. The heads of two adult giraffes and one fetus were used in this study. The lips were well developed, the upper one was predominant and dorsally flattened near […]
Vascular system of giraffe
Both the discussions of the vascular system of the giraffe…mention venous valves, but both overlook the special ‘seried’ valves found at the entry of major tributaries into the axillary and brachial veins, though not into the jugular. Fewer occur in the closely-related okapi and some in jugular and femoral veins of the bactrian camel.
Robert Goetz: A pioneer of the study of the physiology of animals in the wild
Studying the physiology and behaviour of free-living wild animals was impossible until the technology to capture wild animals and to make measurements in the field was developed. A pioneer in this field was Robert H. Goetz who, having completed medical degrees in Germany and Switzerland, took up an appointment as a research scientist in the […]
The structure and function of giraffe jugular vein valves
When a giraffe (Giraffa camelopardalis) lowers its head to drink, blood could enter the jugular vein from the inferior vena cava or regurgitate from the jugular veins into the cranial veins. We investigated the anatomy of jugular valves in giraffes to establish if they could prevent either of these regurgitations. Jugular vein length and intervalve […]