Search the Article Database:

Search our library of articles, papers and other published materials. You can use keywords or boolean-style search:

Giraffe genome sequence reveals clues to its unique morphology and physiology

The origins of giraffe’s imposing stature and associated cardiovascular adaptations are unknown. Okapi, which lacks these unique features, is giraffe’s closest relative and provides a useful comparison, to identify genetic variation underlying giraffe’s long neck and cardiovascular system. The genomes of giraffe and okapi were sequenced, and through comparative analyses genes and pathways were identified that exhibit unique genetic changes and likely contribute to giraffe’s unique features. Some of these genes are in the HOX, NOTCH and FGF signalling pathways,

View Details + Download

Fossil evidence and stages of elongation of the Giraffa camelopardalis neck

Several evolutionary theories have been proposed to explain the adaptation of the long giraffe neck; however, few studies examine the fossil cervical vertebrae. We incorporate extinct giraffids, and the okapi and giraffe cervical vertebral specimens in a comprehensive analysis of the anatomy and elongation of the neck. We establish and evaluate 20 character states that relate to general, cranial and caudal vertebral lengthening, and calculate a length-to-width ratio to measure the relative slenderness of the vertebrae. Our sample includes cervical

View Details + Download

Organization of cholinergic, putative catecholaminergic and serotonergic nuclei in the diencephalon, mibrain and pons of sub-adult male giraffes

The current study describes the nuclear organization and neuronal morphology of the cholinergic, putative catecholaminergic and serotonergic systems within the diencephalon, midbrain and pons of the giraffe using immunohistochemistry for choline acetyltransferase, tyrosine hydroxylase and serotonin. The giraffe has a unique phenotype (the long neck), a large brain (over 500 g) and is a non-domesticated animal, while previous studies examining the brains of other Artiodactyls have all been undertaken on domesticated animals. The aim of the present study was to

View Details + Download

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 may present challenges to this neural pathway in terms of the metabolism required for correct functioning and maintenance of potentially very long axons. The spinal

View Details + Download

Karyotype evolution of giraffes (Giraffa camelopardalis) revealed by cross-species chromosome painting with Chinese muntjac (Muntiacus reevesi) and human (Homo sapiens) paints

Considering the giraffe ( Giraffa camelopardalis,  GCA, 2n = 30) as a primitive species, its comparative genomic data are critical for our understanding of the karyotype evolution of pecorans. Here, we have established genome-wide chromosomal homologies between giraffe, Chinese muntjac ( Muntiacus reevesi,  MRE, 2n = 46) and human ( Homo sapiens, HSA, 2n = 46) with whole sets of chromosome-specific paints from Chinese muntjac and human, in addition to providing a high-resolution G-banding karyotype of giraffe. Chinese muntjac and

View Details + Download

Sexual selection is not the origin of long necks in giraffes

The evolutionary origin of the long neck of giraffes is enigmatic. One theory (the ‘sexual selection’ theory) is that their shape evolved because males use their necks and heads to achieve sexual dominance. Support for this theory would be that males invest more in neck and head growth than do females. We have investigated this hypothesis in 17 male and 21 female giraffes with body masses ranging from juvenile to mature animals, by measuring head mass, neck mass, neck and

View Details + Download

On the origin, evolution and phylogeny of giraffes Giraffa camelopardalis

The origin, phylogeny, and evolution of modern giraffes (Giraffa camelopardalis) is obscure. We review here the literature and conclude that the proximate ancestors of modern giraffes probably evolved in southern central Europe about 8 million years ago (Mya). These ancestors appear to have arisen from the gelocid ancestral assemblage of 20–25 Mya via the family Palaeomerycidae. From the palaeomerycids arose the Antilocaprinae (Pronghorns) via the subfamily Dromomerycinae, and two subfamilies of giraffids, the Climacoceratidae and Canthumerycidae. The terminal genus of

View Details + Download
© All articles are copyrighted to the original authors/publishers unless otherwise stated. Any PDF files provided by the GRC are for personal use only and may not be reproduced. The files reflect the holdings of the GRC library and only contain pages relevant to giraffe study, and may not be complete. Users are obliged to follow all copyright restrictions.

Privacy Policy Cookie Policy