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- Ah-King, Malin, 1973-, et al.
(författare)
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Phylogenetic analysis of twinning in Callitrichinae
- 2000
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Ingår i: American Journal of Primatology. - 0275-2565 .- 1098-2345. ; 51:2, s. 135-146
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Tidskriftsartikel (refereegranskat)abstract
- The callitrichines are known for twinning and for a communal rearingsystem in which all or most group members help care for the offspring.The origin of twinning has been the subject of much speculation. In thisstudy predictions from earlier hypotheses are tested on the basis of twoalternative phylogenetic trees. From this analysis we infer that helpingbehavior and male care preceded the origin of twinning, and that thesetraits did not coevolve with, but might have been important prerequisitesfor twinning in callitrichines. Small body size does not necessarilyresult in twinning, although it might still have been a prerequisite forits evolution. Gum feeding was an ecological change which evolved alongwith twinning. If nutrition was a limiting factor in the number of offspringproduced, then the use of a new feeding resource could have beencrucial for the origin of twinning in callitrichines. According to one of thetwo alternative solutions inferred by the total evidence tree, and in accordancewith the morphological tree, semi-annual breeding appears inthe marmosets together with specialization in gum feeding. The fact thatgums are available for these monkeys all year may have facilitated semiannualbreeding. We suggest that the exploitation of gums as a feedingresource could have been the decisive factor in the increase of the reproductiverate by twinning and by semi-annual breeding.
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| 3. |
- Tullberg, Birgitta S., et al.
(författare)
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Phylogenetic reconstruction of the parental-care system in the ancestors of birds
- 2002
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Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences. - 0962-8436 .- 1471-2970. ; 357, s. 251-257
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Tidskriftsartikel (refereegranskat)abstract
- Due to the controversy surrounding incipient avian parental care, ancestral parental care systems werereconstructed in a phylogeny including major extant amniote lineages. Using two different resolutions forthe basal avian branches, transitions between the states no care, female care, biparental care and malecare were inferred for the most basal branches of the tree. Uniparental female care was inferred for thelineage to birds and crocodiles. Using a phylogeny where ratites and tinamous branch off early and anordered character-state assumption, a transition to biparental care was inferred for the ancestor of birds.This ancestor could be any organism along the lineage leading from the crocodile–bird split up to modernbirds, not necessarily the original bird. We discuss the support for alternative avian phylogenies and thehomology in parental care between crocodiles and birds. We suggest that the phylogenetic pattern shouldbe used as a starting point for a more detailed analysis of parental care systems in birds and their relatives.
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