Match!

Ecology limits the diversity of the Cape flora: Phylogenetics and diversification of the genus Tetraria

Published on Mar 1, 2014in Molecular Phylogenetics and Evolution3.992
· DOI :10.1016/j.ympev.2013.11.017
Jasper A. Slingsby13
Estimated H-index: 13
(UCT: University of Cape Town),
Matthew N. Britton5
Estimated H-index: 5
(University of California, Berkeley),
G. Anthony Verboom21
Estimated H-index: 21
(UCT: University of Cape Town)
Abstract
abstract Understanding the ecology and evolution of the hyper-diverse Cape flora is dependent on developing anunderstanding of its component parts, best epitomized by the Cape floral clades that have diversified andare largely endemic to the region. Here we employ a new dated phylogenetic hypothesis for the sedgegenus Tetraria, one of the smaller Cape floral clades, to develop an understanding of timing and ratesof diversification in the group. Specifically, we test whether diversification in Tetraria slowed as the num-ber of extant lineages increased, suggesting that available ecological niche space has become increasinglysaturated through time. The radiation of Tetraria began approximately 18 million years ago, concordantwith that of many other Cape clades. Diversification rates in the genus showed no drastic shifts inresponse to major environmental changes, but declined as lineage diversity accumulated, indicative ofecological limitation on speciation rates. This allows the development of heuristic predictions aboutthe composition of Tetraria assemblages at various spatial scales, and suggests that closely related speciesshould either be ecologically differentiated or have non-overlapping geographic distributions. The ques-tion of whether ecological limitation of diversity is a common phenomenon in other Cape lineages hasimportant implications for our understanding of the evolution and ecology of the contemporary Capeflora as a whole. 2013 Elsevier Inc. All rights reserved.
  • References (84)
  • Citations (15)
📖 Papers frequently viewed together
145 Citations
42 Citations
144 Citations
78% of Scinapse members use related papers. After signing in, all features are FREE.
References84
Newest
126k Citations
#1Lydie M Dupont (University of Bremen)H-Index: 39
#2Hans Peter Linder (UZH: University of Zurich)H-Index: 32
Last. Enno Schefuß (University of Bremen)H-Index: 30
view all 4 authors...
Aim To test whether the radiation of the extremely rich Cape flora is correlated with marine-driven climate change. Location Middle to Late Miocene in the south-east Atlantic and the Benguela Upwelling System (BUS) off the west coast of South Africa. Methods We studied the palynology of the thoroughly dated Middle to Late Miocene sediments of Ocean Drilling Program (ODP) Site 1085 retrieved from the Atlantic off the mouth of the Orange River. Both marine upwelling and terrestrial input are recor...
62 CitationsSource
Last. Anton Pauw (Stellenbosch University)H-Index: 22
view all 8 authors...
AbstractBoth pollination by animals and mycorrhizal symbioses with fungi are believed to have been important for the diversification of flowering plants. However, the mechanisms by which these above- and belowground mutualisms affect plant speciation and coexistence remain obscure. We provide evidence that shifts in pollination traits are important for both speciation and coexistence in a diverse group of orchids, whereas shifts in fungal partner are important for coexistence but not for speciat...
133 CitationsSource
#1Benny Bytebier (UKZN: University of KwaZulu-Natal)H-Index: 17
#2Alexandre Antonelli (UZH: University of Zurich)H-Index: 31
Last. H. Peter Linder (UZH: University of Zurich)H-Index: 38
view all 4 authors...
Fire may have been a crucial component in the evolution of the Cape flora of South Africa, a region characterized by outstanding levels of species richness and endemism. However, there is, to date, no critical assessment of the age of the modern fire regime in this biome. Here, we exploit the presence of two obligate post-fire flowering clades in the orchid genus Disa, in conjunction with a robust, well-sampled and dated molecular phylogeny, to estimate the age by which fire must have been prese...
63 CitationsSource
#1Luis M. Valente (Imperial College London)H-Index: 18
#2Gail Reeves (Imperial College London)H-Index: 1
Last. Timothy G. Barraclough (Imperial College London)H-Index: 45
view all 8 authors...
The Cape region of South Africa is a hotspot of flowering plant biodiversity. However, the reasons why levels of diversity and endemism are so high remain obscure. Here, we reconstructed phylogenetic relationships among species in the genus Protea, which has its center of species richness and endemism in the Cape, but also extends through tropical Africa as far as Eritrea and Angola. Contrary to previous views, the Cape is identified as the ancestral area for the radiation of the extant lineages...
94 CitationsSource
#1Michael D. Pirie (Stellenbosch University)H-Index: 20
#2Aelys M. Humphreys (UZH: University of Zurich)H-Index: 14
Last. H. Peter Linder (UZH: University of Zurich)H-Index: 4
view all 4 authors...
We explore the potential impact of conflicting gene trees on inferences of evolutionary history above the species level. When conflict between gene trees is discovered, it is common practice either to analyze the data separately or to combine the data having excluded the conflicting taxa or data partitions for those taxa (which are then recoded as missing). We demonstrate an alternative approach, which involves duplicating conflicting taxa in the matrix, such that each duplicate is represented b...
53 CitationsSource
#1Surendra Kumar (University of Oslo)H-Index: 10
#2Åsmund Skjæveland (University of Oslo)H-Index: 8
Last. Kamran Shalchian-Tabrizi (University of Oslo)H-Index: 32
view all 9 authors...
Background Large multigene sequence alignments have over recent years been increasingly employed for phylogenomic reconstruction of the eukaryote tree of life. Such supermatrices of sequence data are preferred over single gene alignments as they contain vastly more information about ancient sequence characteristics, and are thus more suitable for resolving deeply diverging relationships. However, as alignments are expanded, increasingly numbers of sites with misleading phylogenetic information a...
205 CitationsSource
#1L. Lacey Knowles (UM: University of Michigan)H-Index: 39
Discord among the gene trees of multilocus data has motivated the development of phylogenetic approaches that account for gene-tree heterogeneity in the estimation procedure. Rather than equating a gene tree with the phylogenetic history, the new approaches explicitly consider the relationships between gene trees and the underlying history of species divergence, providing direct estimates of species trees (Fig. 1). The inherent appeal of these approaches is 2-fold. Incorporating information cont...
145 CitationsSource
#1Selena Y. Smith (RHUL: Royal Holloway, University of London)H-Index: 19
#2Margaret E. Collinson (RHUL: Royal Holloway, University of London)H-Index: 44
Last. Marco Stampanoni (ETH Zurich)H-Index: 48
view all 6 authors...
: The sedges (family Cyperaceae) are an economically and ecologically important monocot group dating back at least to the Paleocene. While modern genera are mostly unknown before the Oligocene, several extinct taxa are recognized as the earliest sedges. Their affinities have been unclear until now, because they are found as isolated, often abraded fruits or endocarps. Exceptionally preserved sedge fossils from the Middle Eocene of Messel, Germany yield more characters for identification. Fossil ...
22 CitationsSource
#1Daniel L. Rabosky (Cornell University)H-Index: 39
Diversification rate is one of the most important metrics in macroecological and macroevolutionary studies. Here I demonstrate that diversification analyses can be misleading when researchers assume that diversity increases unbounded through time, as is typical in molecular phylogenetic studies. If clade diversity is regulated by ecological factors, then species richness may be independent of clade age and it may not be possible to infer the rate at which diversity arose. This has substantial co...
312 CitationsSource
Cited By15
Newest
#1G. Anthony Verboom (UCT: University of Cape Town)H-Index: 21
#2Florian C. Boucher (Stellenbosch University)H-Index: 11
Last. William A. Freyman (University of California, Berkeley)H-Index: 7
view all 5 authors...
: Species selection, the effect of heritable traits in generating between-lineage diversification rate differences, provides a valuable conceptual framework for understanding the relationship between traits, diversification and phylogenetic tree shape. An important challenge, however, is that the nature of real diversification landscapes - curves or surfaces which describe the propensity of species-level lineages to diversify as a function of one or more traits - remains poorly understood. Here ...
1 CitationsSource
#1Marit van Santen (UZH: University of Zurich)H-Index: 1
#2Hans Peter Linder (UZH: University of Zurich)H-Index: 32
Abstract The Cape flora is compositionally biased, being dominated by a few fynbos clades (such as Iridaceae, Ericaceae, Proteaceae and Restionaceae) that make up major part of the distinct heathland vegetation in the Cape Floristic Region. Uncertainty exists concerning what excluded the subtropical to tropical palm-dominated woodland/forest vegetation that was the dominant component in the CFR in the Paleocene and allowed the fynbos clades, which are largely derived from outside Africa, to esta...
2 CitationsSource
#1Ilias Semmouri (UGent: Ghent University)H-Index: 2
#2Kenneth Bauters (UGent: Ghent University)H-Index: 6
Last. Isabel Larridon (UGent: Ghent University)H-Index: 9
view all 6 authors...
Despite recent advances in molecular phylogenetic studies, deep evolutionary relationships in Cyperaceae are still not entirely resolved. Reduction of floral morphology and complex inflorescences pose difficulties to unravel relationships based on morphology alone. One of the most phylogenetically informative structures in Cyperaceae are the embryos. The utility of embryo characters and types in Cyperaceae systematics is reviewed in a molecular phylogenetic context using a DNA supermatrix incorp...
3 CitationsSource
#1Ingrid Olivares (UZH: University of Zurich)H-Index: 1
#2Dirk Nikolaus Karger (UZH: University of Zurich)H-Index: 11
Last. Michael Kessler (UZH: University of Zurich)H-Index: 37
view all 3 authors...
Is there a maximum number of species that can coexist? Intuitively, we assume an upper limit to the number of species in a given assemblage, or that a lineage can produce, but defining and testing this limit has proven problematic. Herein, we first outline seven general challenges of studies on species saturation, most of which are independent of the actual method used to assess saturation. Among these are the challenge of defining saturation conceptually and operationally, the importance of set...
1 CitationsSource
#1Isabel Larridon (UGent: Ghent University)H-Index: 9
#2G.A. Verboom (UCT: University of Cape Town)H-Index: 2
Last. A.M. Muasya (UCT: University of Cape Town)H-Index: 6
view all 3 authors...
Abstract Tetraria as currently circumscribed still is a polyphyletic genus restricted to the southern hemisphere. Besides several small independent evolutionary lineages, two larger multispecies lineages have been recognised from South Africa, identifiable by key morphological differences: the c. 30 Tetraria species in the Tricostularia clade tribe Schoeneae have noded culms and a reticulate tunic surrounding the culm base, while the c. 17 Tetraria species in the Schoenus clade of tribe Schoenea...
3 CitationsSource
#1Isabel Larridon (UGent: Ghent University)H-Index: 9
#2Kenneth Bauters (UGent: Ghent University)H-Index: 6
Last. Paul Goetghebeur (UGent: Ghent University)H-Index: 23
view all 10 authors...
Abstract We investigated the monophyly of Costularia (25 species), a genus of tribe Schoeneae (Cyperaceae) that illustrates a remarkable distribution pattern from southeastern Africa, over Madagascar, the Mascarenes and Seychelles, to Malesia and New Caledonia. A further species, Tetraria borneensis , has been suggested to belong to Costularia . Relationships and divergence times were inferred using an existing four marker phylogeny of Cyperaceae tribe Schoeneae expanded with newly generated seq...
4 CitationsSource
#1Yanis Bouchenak-Khelladi (UZH: University of Zurich)H-Index: 12
#2H. Peter Linder (UZH: University of Zurich)H-Index: 38
The enormous species richness in the Cape Floristic Region (CFR) of Southern Africa is the result of numerous radiations, but the temporal progression and possible mechanisms of these radiations are still poorly understood. Here, we explore the macroevolutionary dynamics of the Restionaceae, that include 340 species which are found in all vegetation types in the Cape flora and are ecologically dominant in fynbos. Using an almost complete (i.e. 98%) species-level time calibrated phylogeny and mod...
7 CitationsSource
#1Byron B. Lamont (Curtin University)H-Index: 54
#2Tianhua He (Curtin University)H-Index: 21
Abstract Knowing the environments under which biota have evolved is essential for understanding the functional traits that they possess. Here, we ask when a Mediterranean-type climate (MTC) originated in Western Australia that might help to explain some of its special plant adaptations to summer drought and heat, mild wet winters and intense summer fires. Periodic drought and fire can be traced back to the Cretaceous in southwestern Australia (SWA) but its seasonality is unknown. Previous estima...
6 CitationsSource
#1T.L. Elliott (UdeM: Université de Montréal)H-Index: 2
#2A.M. Muasya (UCT: University of Cape Town)H-Index: 6
Abstract Tetraria – an austral genus with 54 currently accepted species – is polyphyletic, with species located across at least three different clades of the Schoeneae tribe of Cyperaceae. The small African endemic genus Epischoenus is embedded within one of these clades—the Schoenus clade of Tetraria . The majority of species in two of the major clades of Tetraria (the Tricostularia and Schoenus clades) are endemic to the Cape Floristic Region of southern Africa. Species in the Tricostularia cl...
7 CitationsSource
#1Richard M. Cowling (NMU: Nelson Mandela Metropolitan University)H-Index: 81
#2Peter L. Bradshaw (NMU: Nelson Mandela Metropolitan University)H-Index: 5
Last. Félix Forest (Royal Botanic Gardens)H-Index: 33
view all 4 authors...
It has been known for many decades that the diversity of clades endemic to the Greater Cape Floristic Region (GCFR) declines along a longitudinal (west-east) gradient, in concert with a reduction in the proportion of winter rainfall. In honour of the pioneering work by Margaret Levyns, we recognise this pattern as Levyns’ Law, and illustrate it with distribution data for 23 speciose endemic clades. All patterns were consistent with Levyns’ Law. Here we assess explanations for Levyns’ Law in term...
9 CitationsSource