Taxonomic decomposition of the latitudinal gradient in species diversity of North American floras

Michael D. Weiser, Nathan G. Swenson, Brian Enquist, Sean t. Michaletz, Robert B. Waide, Jizhong Zhou, Michael Kaspari

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Aim: To test the latitudinal gradient in plant species diversity for self-similarity across taxonomic scales and amongst taxa. Location: North America. Methods: We used species richness data from 245 local vascular plant floras to quantify the slope and shape of the latitudinal gradients in species diversity (LGSD) across all plant species as well as within each family and order. We calculated the contribution of each family and order to the empirical LGSD. Results: We observed the canonical LGSD when all plants were considered with floras at the lowest latitudes having, on average, 451 more species than floras at the highest latitudes. When considering slope alone, most orders and families showed the expected negative slope, but 31.7% of families and 27.7% of orders showed either no significant relationship between latitude and diversity or a reverse LGSD. Latitudinal patterns of family diversity account for at least 14% of this LGSD. Most orders and families did not show the negative slope and concave-down quadratic shape expected by the pattern for all plant species. A majority of families did not make a significant contribution in species to the LGSD with 53% of plant families contributing little to nothing to the overall gradient. Ten families accounted for more than 70% of the gradient. Two families, the Asteraceae and Fabaceae, contributed a third of the LGSD. Main Conclusions: The empirical LGSD we describe here is a consequence of a gradient in the number of families and diversification within relative few plant families. Macroecological studies typically aim to generate models that are general across taxa with the implicit assumption that the models are general within taxa. Our results strongly suggest that models of the latitudinal gradient in plant species richness that rely on environmental covariates (e.g. temperature, energy) are likely not general across plant taxa.

Original languageEnglish (US)
JournalJournal of Biogeography
DOIs
StateAccepted/In press - Jan 1 2017

Fingerprint

latitudinal gradient
species diversity
flora
decomposition
degradation
family
species richness
vascular plants
vascular plant
Fabaceae
Asteraceae

Keywords

  • Asteraceae
  • Diversity
  • Fabaceae
  • Gradient
  • Latitude
  • Species richness
  • Taxonomic scale

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology

Cite this

Weiser, M. D., Swenson, N. G., Enquist, B., Michaletz, S. T., Waide, R. B., Zhou, J., & Kaspari, M. (Accepted/In press). Taxonomic decomposition of the latitudinal gradient in species diversity of North American floras. Journal of Biogeography. https://doi.org/10.1111/jbi.13131

Taxonomic decomposition of the latitudinal gradient in species diversity of North American floras. / Weiser, Michael D.; Swenson, Nathan G.; Enquist, Brian; Michaletz, Sean t.; Waide, Robert B.; Zhou, Jizhong; Kaspari, Michael.

In: Journal of Biogeography, 01.01.2017.

Research output: Contribution to journalArticle

Weiser, Michael D. ; Swenson, Nathan G. ; Enquist, Brian ; Michaletz, Sean t. ; Waide, Robert B. ; Zhou, Jizhong ; Kaspari, Michael. / Taxonomic decomposition of the latitudinal gradient in species diversity of North American floras. In: Journal of Biogeography. 2017.
@article{f39999ebd4d9480690a9c9b52315e1b3,
title = "Taxonomic decomposition of the latitudinal gradient in species diversity of North American floras",
abstract = "Aim: To test the latitudinal gradient in plant species diversity for self-similarity across taxonomic scales and amongst taxa. Location: North America. Methods: We used species richness data from 245 local vascular plant floras to quantify the slope and shape of the latitudinal gradients in species diversity (LGSD) across all plant species as well as within each family and order. We calculated the contribution of each family and order to the empirical LGSD. Results: We observed the canonical LGSD when all plants were considered with floras at the lowest latitudes having, on average, 451 more species than floras at the highest latitudes. When considering slope alone, most orders and families showed the expected negative slope, but 31.7{\%} of families and 27.7{\%} of orders showed either no significant relationship between latitude and diversity or a reverse LGSD. Latitudinal patterns of family diversity account for at least 14{\%} of this LGSD. Most orders and families did not show the negative slope and concave-down quadratic shape expected by the pattern for all plant species. A majority of families did not make a significant contribution in species to the LGSD with 53{\%} of plant families contributing little to nothing to the overall gradient. Ten families accounted for more than 70{\%} of the gradient. Two families, the Asteraceae and Fabaceae, contributed a third of the LGSD. Main Conclusions: The empirical LGSD we describe here is a consequence of a gradient in the number of families and diversification within relative few plant families. Macroecological studies typically aim to generate models that are general across taxa with the implicit assumption that the models are general within taxa. Our results strongly suggest that models of the latitudinal gradient in plant species richness that rely on environmental covariates (e.g. temperature, energy) are likely not general across plant taxa.",
keywords = "Asteraceae, Diversity, Fabaceae, Gradient, Latitude, Species richness, Taxonomic scale",
author = "Weiser, {Michael D.} and Swenson, {Nathan G.} and Brian Enquist and Michaletz, {Sean t.} and Waide, {Robert B.} and Jizhong Zhou and Michael Kaspari",
year = "2017",
month = "1",
day = "1",
doi = "10.1111/jbi.13131",
language = "English (US)",
journal = "Journal of Biogeography",
issn = "0305-0270",
publisher = "Wiley-Blackwell",

}

TY - JOUR

T1 - Taxonomic decomposition of the latitudinal gradient in species diversity of North American floras

AU - Weiser, Michael D.

AU - Swenson, Nathan G.

AU - Enquist, Brian

AU - Michaletz, Sean t.

AU - Waide, Robert B.

AU - Zhou, Jizhong

AU - Kaspari, Michael

PY - 2017/1/1

Y1 - 2017/1/1

N2 - Aim: To test the latitudinal gradient in plant species diversity for self-similarity across taxonomic scales and amongst taxa. Location: North America. Methods: We used species richness data from 245 local vascular plant floras to quantify the slope and shape of the latitudinal gradients in species diversity (LGSD) across all plant species as well as within each family and order. We calculated the contribution of each family and order to the empirical LGSD. Results: We observed the canonical LGSD when all plants were considered with floras at the lowest latitudes having, on average, 451 more species than floras at the highest latitudes. When considering slope alone, most orders and families showed the expected negative slope, but 31.7% of families and 27.7% of orders showed either no significant relationship between latitude and diversity or a reverse LGSD. Latitudinal patterns of family diversity account for at least 14% of this LGSD. Most orders and families did not show the negative slope and concave-down quadratic shape expected by the pattern for all plant species. A majority of families did not make a significant contribution in species to the LGSD with 53% of plant families contributing little to nothing to the overall gradient. Ten families accounted for more than 70% of the gradient. Two families, the Asteraceae and Fabaceae, contributed a third of the LGSD. Main Conclusions: The empirical LGSD we describe here is a consequence of a gradient in the number of families and diversification within relative few plant families. Macroecological studies typically aim to generate models that are general across taxa with the implicit assumption that the models are general within taxa. Our results strongly suggest that models of the latitudinal gradient in plant species richness that rely on environmental covariates (e.g. temperature, energy) are likely not general across plant taxa.

AB - Aim: To test the latitudinal gradient in plant species diversity for self-similarity across taxonomic scales and amongst taxa. Location: North America. Methods: We used species richness data from 245 local vascular plant floras to quantify the slope and shape of the latitudinal gradients in species diversity (LGSD) across all plant species as well as within each family and order. We calculated the contribution of each family and order to the empirical LGSD. Results: We observed the canonical LGSD when all plants were considered with floras at the lowest latitudes having, on average, 451 more species than floras at the highest latitudes. When considering slope alone, most orders and families showed the expected negative slope, but 31.7% of families and 27.7% of orders showed either no significant relationship between latitude and diversity or a reverse LGSD. Latitudinal patterns of family diversity account for at least 14% of this LGSD. Most orders and families did not show the negative slope and concave-down quadratic shape expected by the pattern for all plant species. A majority of families did not make a significant contribution in species to the LGSD with 53% of plant families contributing little to nothing to the overall gradient. Ten families accounted for more than 70% of the gradient. Two families, the Asteraceae and Fabaceae, contributed a third of the LGSD. Main Conclusions: The empirical LGSD we describe here is a consequence of a gradient in the number of families and diversification within relative few plant families. Macroecological studies typically aim to generate models that are general across taxa with the implicit assumption that the models are general within taxa. Our results strongly suggest that models of the latitudinal gradient in plant species richness that rely on environmental covariates (e.g. temperature, energy) are likely not general across plant taxa.

KW - Asteraceae

KW - Diversity

KW - Fabaceae

KW - Gradient

KW - Latitude

KW - Species richness

KW - Taxonomic scale

UR - http://www.scopus.com/inward/record.url?scp=85034256028&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85034256028&partnerID=8YFLogxK

U2 - 10.1111/jbi.13131

DO - 10.1111/jbi.13131

M3 - Article

JO - Journal of Biogeography

JF - Journal of Biogeography

SN - 0305-0270

ER -