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Fred B. Bercovitch - One of the best experts on this subject based on the ideXlab platform.
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How many species of giraffe are there
Current Biology, 2017Co-Authors: Fred B. Bercovitch, Philip S. M. Berry, Anne Innis Dagg, Francois Deacon, John Doherty, Derek E. Lee, Frédéric Mineur, Zoe Muller, Rob Ogden, Russell SeymourAbstract:In a recent paper in Current Biology, Fennessy and colleagues [1] conclude that there are four species of giraffe and that their numbers are declining in Africa. Giraffes (Giraffa camelopardalis) are presently classified as one species, with nine subspecies, which are considered 'Vulnerable' on the IUCN Red List [2]. The present consensus of one species divided into nine subspecies has previously been questioned (Supplemental information), and Fennessy and colleagues [1] provide another viewpoint on giraffe taxonomy. The fundamental reason for different taxonomic interpretations is that they are based upon different datasets that adopt different statistical techniques and follow different criteria for nomenclature.
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Population census of Thornicroft's giraffe Giraffa camelopardalis thornicrofti in Zambia, 1973−2003: conservation reassessment required
Oryx, 2016Co-Authors: Philip S. M. Berry, Fred B. BercovitchAbstract:Thornicroft's giraffe Giraffa camelopardalis thornicrofti is limited in distribution to a single population resident in the Luangwa Valley, Zambia. During 1973−2003 regular counts were recorded along the Luangwa River in the core section of the subspecies’ range. In 2013 we conducted a count in the same region for comparison with the earlier survey results. During the 30-year period 1973−2003 the giraffe index (no. of individuals per km surveyed) was relatively stable, with an increase in 1994 and 1995 coinciding with an influx of giraffes to the west bank following an exceptionally reduced flow of the Luangwa River. The mean giraffe index during this period was 0.51 km −1 , whereas the 2013 count yielded an index of 0.44 km −1 . Given the limited range of the Thornicroft's giraffe, we estimate that the population comprises c. 500–600 individuals.
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population census of thornicroft s giraffe Giraffa camelopardalis thornicrofti in zambia 1973 2003 conservation reassessment required
Oryx, 2016Co-Authors: Philip S. M. Berry, Fred B. BercovitchAbstract:Thornicroft's giraffe Giraffa camelopardalis thornicrofti is limited in distribution to a single population resident in the Luangwa Valley, Zambia. During 1973−2003 regular counts were recorded along the Luangwa River in the core section of the subspecies’ range. In 2013 we conducted a count in the same region for comparison with the earlier survey results. During the 30-year period 1973−2003 the giraffe index (no. of individuals per km surveyed) was relatively stable, with an increase in 1994 and 1995 coinciding with an influx of giraffes to the west bank following an exceptionally reduced flow of the Luangwa River. The mean giraffe index during this period was 0.51 km −1 , whereas the 2013 count yielded an index of 0.44 km −1 . Given the limited range of the Thornicroft's giraffe, we estimate that the population comprises c. 500–600 individuals.
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Concurrent Pregnancy and Lactation in Wild Giraffes (Giraffa camelopardalis)
African Zoology, 2015Co-Authors: Francois Deacon, Pierre J Nel, Fred B. BercovitchAbstract:Lactation boosts reproductive costs by depleting maternal condition and delaying subsequent conception. However, some evidence suggests that giraffes (Giraffa camelopardalis) have evolved a mechanism to minimise the time allocated to suckling-induced suppression of ovulation. Here, we show for the first time that wild giraffe cows are impregnated while nursing a young calf. We suggest that a trio of traits (non-seasonal breeding, slow embryonic development and rapid calf growth) have promoted this unusual and flexible female reproductive strategy.
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Short Communication Concurrent pregnancy and lactation in wild giraffes (Giraffa camelopardalis)
2015Co-Authors: Francois Deacon, Pierre J Nel, Fred B. BercovitchAbstract:Lactation boosts reproductive costs by depleting maternal condition and delaying subsequent conception. However, some evidence suggests that giraffes (Giraffa camelopardalis) have evolved a mechanism to minimise the time allocated to suckling-induced suppression of ovulation. Here, we show for the first time that wild giraffe cows are impregnated while nursing a young calf. We suggest that a trio of traits (non-seasonal breeding, slow embryonic development and rapid calf growth) have promoted this unusual and flexible female reproductive strategy.
Axel Janke - One of the best experts on this subject based on the ideXlab platform.
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Species assignment and conservation genetics of giraffe in the Republic of Malawi
Conservation Genetics, 2019Co-Authors: Sven Winter, Julian Fennessy, Raphael T. F. Coimbra, Anna Bronec, Craig Hay, Amanda L. Salb, Axel JankeAbstract:Historically, giraffe have been translocated across Africa to supplement extant populations, reintroduce extinct populations or to establish new populations, often for conservation and tourism. Such faunal relocations were often carried out disregarding taxonomic affiliation. Today, the small giraffe populations in the Republic of Malawi are assumed to consist of South African giraffe (Giraffa Giraffa Giraffa), which have likely descended from five individuals translocated from Imire Game Park (Zimbabwe) to Nyala Game Park (Malawi) in 1993. However, during the last 25 years, unknown additional translocations, migrations or unrecognized local populations of potential Masai giraffe (Giraffa tippelskirchi) in Malawi may have resulted in introgressive hybridization. Thus, the current taxonomic affiliation for Malawi’s giraffe is uncertain, calling for a genetic assessment to implement further management. We analyzed mitochondrial sequences and nuclear introns for 14 individuals, representing approximately half of the known Malawian population, to genetically determine the (sub)species of giraffe that occur in the Republic of Malawi by comparison with a comprehensive Giraffa dataset. Additionally, we genotyped individuals at ten microsatellite loci to determine the level of inbreeding and potential introgression. All data identify individuals unambiguously as South African giraffe, although two individuals shared a single nuclear allele with Masai giraffe. The low microsatellite genetic variability suggests high inbreeding in the current population. Thus, supplementing Malawi’s giraffe populations with G. g. Giraffa will prevent further loss of their genetic diversity and avoid inbreeding depression.
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Matrilineal population structure and distribution of the Angolan giraffe in the Namib desert and beyond
Ecological Genetics and Genomics, 2018Co-Authors: Sven Winter, Julian Fennessy, Stephanie Fennessy, Axel JankeAbstract:Abstract The distribution maps of giraffe ( Giraffa ) subspecies in southern Africa are based on historical assumptions, yet some populations have likely been misidentified, hindering effective conservation efforts. Particularly, the populations in Zimbabwe are poorly studied, and translocations, such as the 1991 movement of giraffe from Namibia's Etosha National Park to mitigate the human-induced decline of Namibia's desert-dwelling giraffe in the lower Hoanib and Hoarusib Rivers, was concluded without consideration of genotype. Mitochondrial DNA sequence analyses from cytochrome b and control region revealed that instead of the South African giraffe subspecies ( G. Giraffa Giraffa ), the Angolan giraffe ( G. g. angolensis ) occurs in southern Zimbabwe's Bubye Valley Conservancy. Furthermore, Namibia's desert-dwelling giraffe and those from Etosha National Park form distinct matrilineal lineages within the Angolan giraffe subspecies clade. Thus, despite the translocation and proximity of the Etosha National Park, the Etosha giraffe genotype has not spread amongst the desert-dwelling giraffe. Use of mutation rate estimates indicates that there has been no matrilineal exchange between Etosha and the desert-dwelling giraffe for ca. 40,000 years. While philopatry could produce distinct mitochondrial lineages, the short geographical distance and long time involved, makes it more likely that the Etosha giraffe cannot successfully compete with a putatively better adapted desert-dwelling giraffe. The analyses also show that the distribution of the Angolan giraffe extends further eastwards than expected. These findings provide important implications for giraffe conservation, and translocation in particular, which may not always be an effective means of improving genetic diversity.
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Limited Introgression Supports Division of Giraffe into Four Species
bioRxiv, 2018Co-Authors: Sven Winter, Julian Fennessy, Axel JankeAbstract:All giraffe (Giraffa) were previously assigned to a single species (G. camelopardalis) and nine subspecies. However, multi-locus analyses of all subspecies have shown that there are four genetically distinct clades and suggest four giraffe species. This conclusion might not be fully accepted due to limited data and lack of explicit gene flow analyses. Here we present an extended study based on 21 independent nuclear loci from 137 individuals. Explicit gene flow analyses identify less than one migrant per generation, including between the closely related northern and reticulated giraffe. Thus, gene flow analyses and population genetics of the extended dataset confirm four genetically distinct giraffe clades and support four independent giraffe species. The new findings call for a revision of the IUCN classification of giraffe taxonomy. Three of the four species are threatened with extinction, mostly occurring in politically unstable regions, and as such, require the highest conservation support possible.
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Multi-locus Analyses Reveal Four Giraffe Species Instead of One.
Current Biology, 2016Co-Authors: Julian Fennessy, Tobias Bidon, Friederike Reuss, Vikas Kumar, Paul W. Elkan, Maria A. Nilsson, Melita Vamberger, Uwe Fritz, Axel JankeAbstract:Traditionally, one giraffe species and up to eleven subspecies have been recognized [1]; however, nine subspecies are commonly accepted [2]. Even after a century of research, the distinctness of each giraffe subspecies remains unclear, and the genetic variation across their distribution range has been incompletely explored. Recent genetic studies on mtDNA have shown reciprocal monophyly of the matrilines among seven of the nine assumed subspecies [3, 4]. Moreover, until now, genetic analyses have not been applied to biparentally inherited sequence data and did not include data from all nine giraffe subspecies. We sampled natural giraffe populations from across their range in Africa, and for the first time individuals from the nominate subspecies, the Nubian giraffe, Giraffa camelopardalis camelopardalis Linnaeus 1758 [5], were included in a genetic analysis. Coalescence-based multi-locus and population genetic analyses identify at least four separate and monophyletic clades, which should be recognized as four distinct giraffe species under the genetic isolation criterion. Analyses of 190 individuals from maternal and biparental markers support these findings and further suggest subsuming Rothschild's giraffe into the Nubian giraffe, as well as Thornicroft's giraffe into the Masai giraffe [6]. A giraffe survey genome produced valuable data from microsatellites, mobile genetic elements, and accurate divergence time estimates. Our findings provide the most inclusive analysis of giraffe relationships to date and show that their genetic complexity has been underestimated, highlighting the need for greater conservation efforts for the world's tallest mammal.
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mitochondrial sequences reveal a clear separation between angolan and south african giraffe along a cryptic rift valley
BMC Evolutionary Biology, 2014Co-Authors: Friederike Bock, Francois Deacon, Julian Fennessy, Andy Tutchings, Tobias Bidon, Andri Marais, Axel JankeAbstract:Background The current taxonomy of the African giraffe (Giraffa camelopardalis) is primarily based on pelage pattern and geographic distribution, and nine subspecies are currently recognized. Although genetic studies have been conducted, their resolution is low, mainly due to limited sampling. Detailed knowledge about the genetic variation and phylogeography of the South African giraffe (G. c. Giraffa) and the Angolan giraffe (G. c. angolensis) is lacking. We investigate genetic variation among giraffe matrilines by increased sampling, with a focus on giraffe key areas in southern Africa.
Francois Deacon - One of the best experts on this subject based on the ideXlab platform.
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Testicular disorder of sexual development with cryptorchidism, penile hypoplasia and hypospadias in a giraffe (Giraffa camelopardalis Giraffa).
Journal of the South African Veterinary Association, 2020Co-Authors: Janine Meuffels, Francois Deacon, Ilse Luther-binoir, Willem Daffue, Emily P. MitchellAbstract:Disorders of sexual development (DSD) in wild mammals are rarely described. A male South African giraffe ( Giraffa camelopardalis Giraffa ) was identified with bilateral cryptorchidism. The testes were intra-abdominal, smaller and less ovoid than in normal male giraffes. The right testis was situated more cranially than the left and connected to a longer deferent duct with normal ampullae. One distended vesicular gland filled with mucoid material was identified. A short penis, situated in the perineal area, was directed caudally and presented hypospadias. Histologically, testicular hypoplasia was present; the epididymis tubules contained no spermatozoa and the deferent duct and vesicular gland were inflamed. The blood testosterone concentration was 16.27 nmol/L and oestrone sulphate concentration was 0.03 ng/mL. The aetiology of the abnormalities is unknown.
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The South African giraffe Giraffa camelopardalis Giraffa : a conservation success story
Oryx, 2018Co-Authors: Francois Deacon, Andy TutchingsAbstract:Across Africa the majority of giraffe species and subspecies are in decline, whereas the South African giraffe Giraffa camelopardalis Giraffa remains numerous and widespread throughout southern Africa. By 2013 the number of giraffes in South Africa's Kruger National Park had increased by c. 150% compared to 1979 estimates. An even greater increase occurred on many of the estimated 12,000 privately owned game ranches, indicating that private ownership can help to conserve this subspecies. The estimated total population size in South Africa is 21,053–26,919. The challenge now is to implement monitoring and surveillance of G. camelopardalis Giraffa as a conservation priority and to introduce sustainable practices among private owners to increase numbers and genetic variation within in-country subspecies.
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How many species of giraffe are there
Current Biology, 2017Co-Authors: Fred B. Bercovitch, Philip S. M. Berry, Anne Innis Dagg, Francois Deacon, John Doherty, Derek E. Lee, Frédéric Mineur, Zoe Muller, Rob Ogden, Russell SeymourAbstract:In a recent paper in Current Biology, Fennessy and colleagues [1] conclude that there are four species of giraffe and that their numbers are declining in Africa. Giraffes (Giraffa camelopardalis) are presently classified as one species, with nine subspecies, which are considered 'Vulnerable' on the IUCN Red List [2]. The present consensus of one species divided into nine subspecies has previously been questioned (Supplemental information), and Fennessy and colleagues [1] provide another viewpoint on giraffe taxonomy. The fundamental reason for different taxonomic interpretations is that they are based upon different datasets that adopt different statistical techniques and follow different criteria for nomenclature.
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Concurrent Pregnancy and Lactation in Wild Giraffes (Giraffa camelopardalis)
African Zoology, 2015Co-Authors: Francois Deacon, Pierre J Nel, Fred B. BercovitchAbstract:Lactation boosts reproductive costs by depleting maternal condition and delaying subsequent conception. However, some evidence suggests that giraffes (Giraffa camelopardalis) have evolved a mechanism to minimise the time allocated to suckling-induced suppression of ovulation. Here, we show for the first time that wild giraffe cows are impregnated while nursing a young calf. We suggest that a trio of traits (non-seasonal breeding, slow embryonic development and rapid calf growth) have promoted this unusual and flexible female reproductive strategy.
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Short Communication Concurrent pregnancy and lactation in wild giraffes (Giraffa camelopardalis)
2015Co-Authors: Francois Deacon, Pierre J Nel, Fred B. BercovitchAbstract:Lactation boosts reproductive costs by depleting maternal condition and delaying subsequent conception. However, some evidence suggests that giraffes (Giraffa camelopardalis) have evolved a mechanism to minimise the time allocated to suckling-induced suppression of ovulation. Here, we show for the first time that wild giraffe cows are impregnated while nursing a young calf. We suggest that a trio of traits (non-seasonal breeding, slow embryonic development and rapid calf growth) have promoted this unusual and flexible female reproductive strategy.
Julian Fennessy - One of the best experts on this subject based on the ideXlab platform.
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Species assignment and conservation genetics of giraffe in the Republic of Malawi
Conservation Genetics, 2019Co-Authors: Sven Winter, Julian Fennessy, Raphael T. F. Coimbra, Anna Bronec, Craig Hay, Amanda L. Salb, Axel JankeAbstract:Historically, giraffe have been translocated across Africa to supplement extant populations, reintroduce extinct populations or to establish new populations, often for conservation and tourism. Such faunal relocations were often carried out disregarding taxonomic affiliation. Today, the small giraffe populations in the Republic of Malawi are assumed to consist of South African giraffe (Giraffa Giraffa Giraffa), which have likely descended from five individuals translocated from Imire Game Park (Zimbabwe) to Nyala Game Park (Malawi) in 1993. However, during the last 25 years, unknown additional translocations, migrations or unrecognized local populations of potential Masai giraffe (Giraffa tippelskirchi) in Malawi may have resulted in introgressive hybridization. Thus, the current taxonomic affiliation for Malawi’s giraffe is uncertain, calling for a genetic assessment to implement further management. We analyzed mitochondrial sequences and nuclear introns for 14 individuals, representing approximately half of the known Malawian population, to genetically determine the (sub)species of giraffe that occur in the Republic of Malawi by comparison with a comprehensive Giraffa dataset. Additionally, we genotyped individuals at ten microsatellite loci to determine the level of inbreeding and potential introgression. All data identify individuals unambiguously as South African giraffe, although two individuals shared a single nuclear allele with Masai giraffe. The low microsatellite genetic variability suggests high inbreeding in the current population. Thus, supplementing Malawi’s giraffe populations with G. g. Giraffa will prevent further loss of their genetic diversity and avoid inbreeding depression.
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Matrilineal population structure and distribution of the Angolan giraffe in the Namib desert and beyond
Ecological Genetics and Genomics, 2018Co-Authors: Sven Winter, Julian Fennessy, Stephanie Fennessy, Axel JankeAbstract:Abstract The distribution maps of giraffe ( Giraffa ) subspecies in southern Africa are based on historical assumptions, yet some populations have likely been misidentified, hindering effective conservation efforts. Particularly, the populations in Zimbabwe are poorly studied, and translocations, such as the 1991 movement of giraffe from Namibia's Etosha National Park to mitigate the human-induced decline of Namibia's desert-dwelling giraffe in the lower Hoanib and Hoarusib Rivers, was concluded without consideration of genotype. Mitochondrial DNA sequence analyses from cytochrome b and control region revealed that instead of the South African giraffe subspecies ( G. Giraffa Giraffa ), the Angolan giraffe ( G. g. angolensis ) occurs in southern Zimbabwe's Bubye Valley Conservancy. Furthermore, Namibia's desert-dwelling giraffe and those from Etosha National Park form distinct matrilineal lineages within the Angolan giraffe subspecies clade. Thus, despite the translocation and proximity of the Etosha National Park, the Etosha giraffe genotype has not spread amongst the desert-dwelling giraffe. Use of mutation rate estimates indicates that there has been no matrilineal exchange between Etosha and the desert-dwelling giraffe for ca. 40,000 years. While philopatry could produce distinct mitochondrial lineages, the short geographical distance and long time involved, makes it more likely that the Etosha giraffe cannot successfully compete with a putatively better adapted desert-dwelling giraffe. The analyses also show that the distribution of the Angolan giraffe extends further eastwards than expected. These findings provide important implications for giraffe conservation, and translocation in particular, which may not always be an effective means of improving genetic diversity.
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Limited Introgression Supports Division of Giraffe into Four Species
bioRxiv, 2018Co-Authors: Sven Winter, Julian Fennessy, Axel JankeAbstract:All giraffe (Giraffa) were previously assigned to a single species (G. camelopardalis) and nine subspecies. However, multi-locus analyses of all subspecies have shown that there are four genetically distinct clades and suggest four giraffe species. This conclusion might not be fully accepted due to limited data and lack of explicit gene flow analyses. Here we present an extended study based on 21 independent nuclear loci from 137 individuals. Explicit gene flow analyses identify less than one migrant per generation, including between the closely related northern and reticulated giraffe. Thus, gene flow analyses and population genetics of the extended dataset confirm four genetically distinct giraffe clades and support four independent giraffe species. The new findings call for a revision of the IUCN classification of giraffe taxonomy. Three of the four species are threatened with extinction, mostly occurring in politically unstable regions, and as such, require the highest conservation support possible.
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Multi-locus Analyses Reveal Four Giraffe Species Instead of One.
Current Biology, 2016Co-Authors: Julian Fennessy, Tobias Bidon, Friederike Reuss, Vikas Kumar, Paul W. Elkan, Maria A. Nilsson, Melita Vamberger, Uwe Fritz, Axel JankeAbstract:Traditionally, one giraffe species and up to eleven subspecies have been recognized [1]; however, nine subspecies are commonly accepted [2]. Even after a century of research, the distinctness of each giraffe subspecies remains unclear, and the genetic variation across their distribution range has been incompletely explored. Recent genetic studies on mtDNA have shown reciprocal monophyly of the matrilines among seven of the nine assumed subspecies [3, 4]. Moreover, until now, genetic analyses have not been applied to biparentally inherited sequence data and did not include data from all nine giraffe subspecies. We sampled natural giraffe populations from across their range in Africa, and for the first time individuals from the nominate subspecies, the Nubian giraffe, Giraffa camelopardalis camelopardalis Linnaeus 1758 [5], were included in a genetic analysis. Coalescence-based multi-locus and population genetic analyses identify at least four separate and monophyletic clades, which should be recognized as four distinct giraffe species under the genetic isolation criterion. Analyses of 190 individuals from maternal and biparental markers support these findings and further suggest subsuming Rothschild's giraffe into the Nubian giraffe, as well as Thornicroft's giraffe into the Masai giraffe [6]. A giraffe survey genome produced valuable data from microsatellites, mobile genetic elements, and accurate divergence time estimates. Our findings provide the most inclusive analysis of giraffe relationships to date and show that their genetic complexity has been underestimated, highlighting the need for greater conservation efforts for the world's tallest mammal.
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mitochondrial sequences reveal a clear separation between angolan and south african giraffe along a cryptic rift valley
BMC Evolutionary Biology, 2014Co-Authors: Friederike Bock, Francois Deacon, Julian Fennessy, Andy Tutchings, Tobias Bidon, Andri Marais, Axel JankeAbstract:Background The current taxonomy of the African giraffe (Giraffa camelopardalis) is primarily based on pelage pattern and geographic distribution, and nine subspecies are currently recognized. Although genetic studies have been conducted, their resolution is low, mainly due to limited sampling. Detailed knowledge about the genetic variation and phylogeography of the South African giraffe (G. c. Giraffa) and the Angolan giraffe (G. c. angolensis) is lacking. We investigate genetic variation among giraffe matrilines by increased sampling, with a focus on giraffe key areas in southern Africa.
Philip S. M. Berry - One of the best experts on this subject based on the ideXlab platform.
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How many species of giraffe are there
Current Biology, 2017Co-Authors: Fred B. Bercovitch, Philip S. M. Berry, Anne Innis Dagg, Francois Deacon, John Doherty, Derek E. Lee, Frédéric Mineur, Zoe Muller, Rob Ogden, Russell SeymourAbstract:In a recent paper in Current Biology, Fennessy and colleagues [1] conclude that there are four species of giraffe and that their numbers are declining in Africa. Giraffes (Giraffa camelopardalis) are presently classified as one species, with nine subspecies, which are considered 'Vulnerable' on the IUCN Red List [2]. The present consensus of one species divided into nine subspecies has previously been questioned (Supplemental information), and Fennessy and colleagues [1] provide another viewpoint on giraffe taxonomy. The fundamental reason for different taxonomic interpretations is that they are based upon different datasets that adopt different statistical techniques and follow different criteria for nomenclature.
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Population census of Thornicroft's giraffe Giraffa camelopardalis thornicrofti in Zambia, 1973−2003: conservation reassessment required
Oryx, 2016Co-Authors: Philip S. M. Berry, Fred B. BercovitchAbstract:Thornicroft's giraffe Giraffa camelopardalis thornicrofti is limited in distribution to a single population resident in the Luangwa Valley, Zambia. During 1973−2003 regular counts were recorded along the Luangwa River in the core section of the subspecies’ range. In 2013 we conducted a count in the same region for comparison with the earlier survey results. During the 30-year period 1973−2003 the giraffe index (no. of individuals per km surveyed) was relatively stable, with an increase in 1994 and 1995 coinciding with an influx of giraffes to the west bank following an exceptionally reduced flow of the Luangwa River. The mean giraffe index during this period was 0.51 km −1 , whereas the 2013 count yielded an index of 0.44 km −1 . Given the limited range of the Thornicroft's giraffe, we estimate that the population comprises c. 500–600 individuals.
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population census of thornicroft s giraffe Giraffa camelopardalis thornicrofti in zambia 1973 2003 conservation reassessment required
Oryx, 2016Co-Authors: Philip S. M. Berry, Fred B. BercovitchAbstract:Thornicroft's giraffe Giraffa camelopardalis thornicrofti is limited in distribution to a single population resident in the Luangwa Valley, Zambia. During 1973−2003 regular counts were recorded along the Luangwa River in the core section of the subspecies’ range. In 2013 we conducted a count in the same region for comparison with the earlier survey results. During the 30-year period 1973−2003 the giraffe index (no. of individuals per km surveyed) was relatively stable, with an increase in 1994 and 1995 coinciding with an influx of giraffes to the west bank following an exceptionally reduced flow of the Luangwa River. The mean giraffe index during this period was 0.51 km −1 , whereas the 2013 count yielded an index of 0.44 km −1 . Given the limited range of the Thornicroft's giraffe, we estimate that the population comprises c. 500–600 individuals.
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herd composition kinship and fission fusion social dynamics among wild giraffe
African Journal of Ecology, 2013Co-Authors: Fred B. Bercovitch, Philip S. M. BerryAbstract:A variety of social systems have evolved as a consequence of competition and cooperation among individuals. Giraffe (Giraffa camelopardalis sp.) societies are an anomaly because the dearth of long-term data has produced two polar perspectives: a loose amalgamation of non-bonded individuals that sometimes coalesce into a herd and a structured social system with a fission–fusion process modifying herd composition within a community. We analysed 34 years of data collected from a population of Thornicroft's giraffe (G. c. thornicrofti, Lydekker 1911) residing in South Luangwa, Zambia, to establish the nature of giraffe society. Our sample consisted of 52 individually recognized animals. We found that giraffe herd composition is based upon long-term social associations that often reflect kinship, with close relatives significantly more likely than non-relatives to establish herds. Mother/offspring dyads had the strongest associations, which persisted for years. Giraffe live in a complex society characterized by marked flexibility in herd size, with about 25% of the variance in herd composition owing to kinship and sex. We suggest that giraffe herds share many characteristics of fission–fusion social systems and propose that sophisticated communication systems are a crucial component regulating subgroup dynamics.