Header

UZH-Logo

Maintenance Infos

Have giant lobelias evolved several times independently? Life form shifts and historical biogeography of the cosmopolitan and highly diverse subfamily Lobelioideae (Campanulaceae)


Antonelli, A (2009). Have giant lobelias evolved several times independently? Life form shifts and historical biogeography of the cosmopolitan and highly diverse subfamily Lobelioideae (Campanulaceae). BMC Biology, 7:82.

Abstract

BACKGROUND: The tendency of animals and plants to independently develop similar features under similar evolutionary pressures - convergence - is a widespread phenomenon in nature. In plants, convergence has been suggested to explain the striking similarity in life form between the giant lobelioids (Campanulaceae, the bellflower family) of Africa and the Hawaiian Islands. Under this assumption these plants would have developed the giant habit from herbaceous ancestors independently, in much the same way as has been suggested for the giant senecios of Africa and the silversword alliance of Hawaii. RESULTS: Phylogenetic analyses based on plastid (rbcL, trnL-F) and nuclear (internal transcribed spacer [ITS]) DNA sequences for 101 species in subfamily Lobelioideae demonstrate that the large lobelioids from eastern Africa the Hawaiian Islands, and also South America, French Polynesia and southeast Asia, form a strongly supported monophyletic group. Ancestral state reconstructions of life form and distribution, taking into account phylogenetic uncertainty, indicate their descent from a woody ancestor that was probably confined to Africa. Molecular dating analyses using Penalized Likelihood and Bayesian relaxed clock approaches, and combining multiple calibration points, estimate their first diversification at approximately 25-33 million years ago (Ma), shortly followed by several long-distance dispersal events that resulted in the current pantropical distribution. CONCLUSION: These results confidently show that lobelioid species, commonly called 'giant', are very closely related and have not developed their giant form from herbaceous ancestors independently. This study, which includes the hitherto largest taxon sampling for subfamily Lobelioideae, highlights the need for a broad phylogenetic framework for testing assumptions about morphological development in general, and convergent evolution in particular.

Abstract

BACKGROUND: The tendency of animals and plants to independently develop similar features under similar evolutionary pressures - convergence - is a widespread phenomenon in nature. In plants, convergence has been suggested to explain the striking similarity in life form between the giant lobelioids (Campanulaceae, the bellflower family) of Africa and the Hawaiian Islands. Under this assumption these plants would have developed the giant habit from herbaceous ancestors independently, in much the same way as has been suggested for the giant senecios of Africa and the silversword alliance of Hawaii. RESULTS: Phylogenetic analyses based on plastid (rbcL, trnL-F) and nuclear (internal transcribed spacer [ITS]) DNA sequences for 101 species in subfamily Lobelioideae demonstrate that the large lobelioids from eastern Africa the Hawaiian Islands, and also South America, French Polynesia and southeast Asia, form a strongly supported monophyletic group. Ancestral state reconstructions of life form and distribution, taking into account phylogenetic uncertainty, indicate their descent from a woody ancestor that was probably confined to Africa. Molecular dating analyses using Penalized Likelihood and Bayesian relaxed clock approaches, and combining multiple calibration points, estimate their first diversification at approximately 25-33 million years ago (Ma), shortly followed by several long-distance dispersal events that resulted in the current pantropical distribution. CONCLUSION: These results confidently show that lobelioid species, commonly called 'giant', are very closely related and have not developed their giant form from herbaceous ancestors independently. This study, which includes the hitherto largest taxon sampling for subfamily Lobelioideae, highlights the need for a broad phylogenetic framework for testing assumptions about morphological development in general, and convergent evolution in particular.

Statistics

Citations

30 citations in Web of Science®
29 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

278 downloads since deposited on 15 Jan 2010
39 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Department of Systematic and Evolutionary Botany
Dewey Decimal Classification:580 Plants (Botany)
Language:English
Date:2009
Deposited On:15 Jan 2010 11:53
Last Modified:03 Aug 2017 15:11
Publisher:BioMed Central
ISSN:1741-7015
Free access at:PubMed ID. An embargo period may apply.
Publisher DOI:https://doi.org/10.1186/1741-7007-7-82
PubMed ID:19941635

Download

Preview Icon on Download
Preview
Content: Published Version
Filetype: PDF
Size: 2MB
View at publisher
Licence: Creative Commons: Attribution 2.0 Generic (CC BY 2.0)

TrendTerms

TrendTerms displays relevant terms of the abstract of this publication and related documents on a map. The terms and their relations were extracted from ZORA using word statistics. Their timelines are taken from ZORA as well. The bubble size of a term is proportional to the number of documents where the term occurs. Red, orange, yellow and green colors are used for terms that occur in the current document; red indicates high interlinkedness of a term with other terms, orange, yellow and green decreasing interlinkedness. Blue is used for terms that have a relation with the terms in this document, but occur in other documents.
You can navigate and zoom the map. Mouse-hovering a term displays its timeline, clicking it yields the associated documents.

Author Collaborations