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• Taxonomic argument: The divisions of species into su bspecies were mainly created by ..,mis;\S in view of the need for nomenclature. In the past, subspecies have often been described basis of minor, arbitrary, equivocal, inconclusive or outdated criteria. For example, minor and external morphological differences (e.g. size, colouration, pelage pattern) have been used. Further shortcomings appear in the methodology used in the past, such as descriptions were often I>ased on very few specimens, synon yms which have not yet been properly sorted and overlap of characteristics between neighbouring subspecies. Because of these IIbodological failures, many described subspecies cannot be validated as they do not correspond to realities but to artificial subdivisions. • Technical argument: Molecular genetic techniques, particularly DNA sequencmg, are SO precise that it is possible to distinguish individuals. This raises the question of how to the arbitrary threshold that fixes the level below which distinctions between the specimens should be ignored (Avise and Ball, 1990; Avise, 1989). With allozyme data, the overlapping ranges of values of genetic distances associated with different taxonomic levels (population, .pecies, species, subgenera) makes it difficult to use these criteria for deciding whether two (or compared taxa should be placed in one or another category (Duplantier et af., 1990). • Biological argument: Some of the proposed reintroduction sites (where the concerned no longer occurs) have been altered to such a degree that animals of the subspecies formerly lIt'upying the area might be less, or only equally, suitable compared to any other subspecies. IIIoreo',er, reintroduced animals of uncertain status (such as subspecific hybrids) may have a higher due to their genetic mixture and consequently increased adaptability. The reintroduction of peregrine falcon Falco perigrinus into the eastern U.S.A. was achieved by releasing young birds from genetic stocks of various geographical origins (Spain, Scotland. Chile. Alaska, the Aleutian Islands. the Queen Charlotte Islands and California). The reintroduction was successful despite the fact that the birds were genetically very different from the aboriginal population (Barclay and Cade, 1983). • Practical argument: Due to the accelerating rate of extinctions, species conservation is increasingly becoming a race against the clock. Considering subspecific taxonomic levels will cost money and time and therefore cause the delay of conservation action in particular reintroduction projects. The arguments in favour of subspecies can be divided into three categories: ethical. phylogenetic and ecological arguments. Ethical argument: The main role of conservation is to maintain biOdi versity . Reintroduction projects should therefore aim to restore former biodive rsity. Reintroduction of an alien subspecies into the range of a native subspecies would decrease biodiversity, except if the historical subspecies is extinct. It has been emphasized by mCN (1987) and different authors (Brambell. 1977; Stanley-Price. 1989) that the animals involved in reintroduction should be the 53
"closest available race to the original stock and preferably be the same race as that previously occurring in the area" (IUCN, 1987). For restocking, the recommendations are even stronger, emphasizing that "only individuals from a similar climatic or ecological zone (should be) used since interbreeding with individuals from an area with a milder climate may interfere with resistant and hardy genotypes on the population's edge" (IUCN, 1987). The guidelines of the Re-introduction SpeCialist Group of IUCN (Re-introduction Specialist Group, 1992) are more specific, recommending that the animals should be of the same taxonomic unit as those which were extirpated and that taxonomic investigation, using molecular genetic studies if necessary, should be undertaken in case of doubt. Depending on the success of the operation, reintroductions can become restocking if the reintroduced animals expand their range and interbreed with remnant local populations. This kind of process, depending on the species' survival, could be irreversible. It implies a responsibility towards future generations, and therefore all possible precautions should be taken. An assessment of the taxonomic status of individuals to be reintroduced and of the local existing or historical subspecies should be a prerequisite to any such programme. Ecological argument: Many species are distributed over a geographical range that encompasses a range of environmental conditions that influence the animals' ability to survive or reproduce. Under these conditions, local populations of the species will often adapt to the local environment (Templeton el aI., 1986). This is of particular importance in species where dispersal is limited. Hybridization between different local populations could result in outbreeding depression, a decrease in fertility and viability of the progeny, and the production of animals with genetic make-ups inappropriate for a given environment (Templeton, 1986). To enhance the success of reintroduction programmes, animals must be well adapted to their environment. The subspecies that previously occurred locally is in all probability the most adapted taxa, except in the case of a drastic and recent change in the environment. A famous example that illustrates the risk of mixing subspecies is the reintroduction of ibex into CzeChoslovakia. Capra ibex ibex from Austria were successfully reintroduced after the extinction of the locally adapted Tatra mountain ibex C. i. ibex, due to overhunting. But, some years later, bezoars C. i. aegagrus from Turkey, and Nubian ibex C. i. flubiafla from the Sinai peninsula were added to reinforce the local herd. The resulting fertile hybrids dropped their kids in February, three months earlier than the pure C. i. ibex population, and the coldest month of the year, resulting in total kid loss. As a consequence, the entire population became extinct (Greig, 1979). Phylogenetic argument: The process of species formation and dynamics includes geographic isolation and genetic differentiation of populations below the species level. The subspecific designation accounts for this process and recognizes the potential of isolated subspecies to acquire ecological adaptations through natural selection, and, in some cases, to become new speCies. It is clear that there is a real problem in assessing the validity of subspecies. However the subspecies concept has a phylogenetic and ecological significance that cannot be ignored. The recent evolution of modern taxonomy and the availability of molecular techniques should provide a more reasonable basis for a proper recognition of evolutionarily significant units (Ryder, 1986). Molecular assays provide access to a specified and usually significant sample of genetic material, whereas 54
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CONSERVATION OF ARABIAN GAZELLES
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• 14 Survey of Gazelle Populatio
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List of Contributors Prof. Abdulaz
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Foreword HRH Prince SAUD AL-FAISAL
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1. Recent Developments in Gazelle C
Page 12 and 13: • April, 1988: Survey of the Fara
Page 14 and 15: - May, 1991: Capture of rheem from
Page 16 and 17: References Abuzinada, A., 1987. Int
Page 18 and 19: until Groves (1983) re-examined the
Page 20 and 21: Figure 2.1 a Figure 2.1 b
Page 22 and 23: Dissatisfaction with the BSC over t
Page 24 and 25: Nixon & Wheeler (1990) are not so d
Page 26 and 27: In order to test the PSC (phylogene
Page 28 and 29: (2) FEMALES Variable gazella cora
Page 30 and 31: two adult male and one adult female
Page 32 and 33: 4 4 * 4 3 2 *33 1 1 * 1 * 2 1 1 I 5
Page 34 and 35: (2) FEMALES Variable G. bennelli (
Page 36 and 37: In the two other equally parsimonio
Page 38 and 39: ufifrons benneui saudiya subguuurcs
Page 40 and 41: By branch-swapping, using Macelade,
Page 42 and 43: On my first visit to AI-Areen, in 1
Page 44 and 45: anch of the premaxilla generally to
Page 46 and 47: J.R., and Morrison-Scott, T.C.S. 19
Page 48 and 49: Aden: 12°50'N, 45°03'E (4 skins,
Page 50 and 51: species is currently the subject of
Page 52 and 53: One area where local people are ins
Page 54 and 55: 4. The Relationship Between Taxonom
Page 56 and 57: 'I1Ie current status of taxonomy Ad
Page 58 and 59: There is much scope for conflict be
Page 60 and 61: The Controversial Subject of Gazell
Page 64 and 65: conventional taxonomic characters t
Page 66 and 67: divergence between the mitochondria
Page 68 and 69: Morphometries: Some morphological c
Page 70 and 71: operative progranune could be set u
Page 72 and 73: museum specimens (data extracted fr
Page 74 and 75: Acknowledgements This work was carr
Page 76 and 77: Lange, 1. 1972. Studien an Gazellen
Page 78 and 79: 6. Modern Techniques in Taxonomy an
Page 80 and 81: protein electrophoresis still a val
Page 82 and 83: "molecular clock") has been establi
Page 84 and 85: Beni~hke, Nombela, J.J., Rodriguez
Page 86 and 87: 7. Chromosonlal Evolution in Gazell
Page 88 and 89: and C. gazella (Vassart et ai., Art
Page 90 and 91: analysis. Systematic relationships
Page 92 and 93: management efforts, whether managem
Page 94 and 95: Kumamoto, A.T., and Bogart, M.H. 19
Page 96 and 97: Table 8.1 Mammalian cells in cultur
Page 98 and 99: genetic diversity in a subspecies w
Page 100 and 101: amount of change between individual
Page 102 and 103: pardus, at positions 38, 61, 64, an
Page 104 and 105: Wildlife Research Center (KKWRC), n
Page 106 and 107: grown m MEM medium supplemented wit
Page 108 and 109: was involved in a V-autosome transl
Page 110 and 111: and heterozygosi ty values found in
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Viegas-Pequignot, E., and Dutrillau
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cellular and molecular biology requ
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structures in terms of visible morp
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Although a Robertsonian translocati
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Groves, c.P. 1969. On the smaller g
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G. bilkis and the dark forms of G.
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survey was carried out in February
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Conservation action: International
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12. Genetics of Saudi dorcas gazell
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Genetic research can clarify the ta
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dorcas gazelles Gazella do rcas ssp
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y less than 2% from each other. How
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Groves, c.P. 1969. On the smaller g
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eflect the truly remarkable output
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• National (central) government p
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past colonial Africa and Asia, and
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• Studies of gazelle growth rates
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References Child, G., and Grainger,
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14. Survey of Gazelle Populations i
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Sony IPS-360 Global Positioning Sys
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1. Mahkshush The gazelle habitat co
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5. Jabal Jandaf A small population
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A slight caveat is required to thes
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• Appoint one local auxiliary ran
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Recommendations on park zoning, man
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'9~ ~~~
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flamingos Phoenicopterus ruber; her
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salt marshes and associated sand du
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Many projects were initiated at KlS
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CG: Taxonomy is the essential backg
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WR: On a mitochondrial DNA basis, w
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CM & AG: We should not forget in si
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- AG: What could the taxon called G
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Gazella dorcas 1) Survey Al-Khunfah
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3 Male mountain gazelle (Thumamah)
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7 Female Arabian sand gazelle (Thum
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