First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia.

Many tropical wet forests are species-rich and have relatively even species frequency distributions. But, dominance by a single canopy species can also occur in tropical wet climates and can remain stable for centuries. These are uncommon globally, with the African wet tropics supporting more such c...

Full description

Bibliographic Details
Main Authors: Aaron D Pan, Bonnie F Jacobs, Rosemary T Bush, Manuel de la Estrella, Friðgeir Grímsson, Patrick S Herendeen, Xander M van der Burgt, Ellen D Currano
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2023-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0279491
_version_ 1797866835471761408
author Aaron D Pan
Bonnie F Jacobs
Rosemary T Bush
Manuel de la Estrella
Friðgeir Grímsson
Patrick S Herendeen
Xander M van der Burgt
Ellen D Currano
author_facet Aaron D Pan
Bonnie F Jacobs
Rosemary T Bush
Manuel de la Estrella
Friðgeir Grímsson
Patrick S Herendeen
Xander M van der Burgt
Ellen D Currano
author_sort Aaron D Pan
collection DOAJ
description Many tropical wet forests are species-rich and have relatively even species frequency distributions. But, dominance by a single canopy species can also occur in tropical wet climates and can remain stable for centuries. These are uncommon globally, with the African wet tropics supporting more such communities than the Neotropics or Southeast Asia. Differences in regional evolutionary histories are implied by biogeography: most of Africa's monodominance-forming species are Amherstieae-tribe legumes; monodominance in Neotropical forests occur among diverse taxonomic groups, often legumes, but rarely Amherstieae, and monodominance in Southeast Asian forests occurs mostly among Dipterocarpaceae species. African monodominant forests have been characterized ecologically and taxonomically, but their deep-time history is unknown despite their significant presence and bottom-up ecological influence on diversity. Herein we describe fossil leaflets of Englerodendron mulugetanum sp. nov., an extinct species of the extant genus Englerodendron (Berlinia Clade, Amherstieae, Detarioideae) from the 21.73 Ma Mush Valley site in Ethiopia. We also document a detailed study of associated legume pollen, which originate from a single taxon sharing characters with more than one extant descendant. Taxonomically, the pollen is most comparable to that from some extant Englerodendron species and supports a likely affiliation with the Englerodendron macrofossils. The Mush Valley site provides the first fossil evidence of a monodominant tropical forest in Africa as represented by leaflets and pollen. Previous studies documented >2400 leaves and leaflets from localities at six stratigraphic levels spanning 50,000-60,000 years of nearly continuous deposition within seven meters of section; all but the basal level contain ≥ 50% E. mulugetanum leaflets. Modern leaf litter studies in African mixed vs. monodominant forests indicates the likelihood of monodominance in the forests that surrounded the Mush paleolake, particularly after the basal level. Thus, we provide an early case for monodominance within the Amherstieae legumes in Africa.
first_indexed 2024-04-09T23:30:38Z
format Article
id doaj.art-50f493ab13384f5998b77c96ed7e0a26
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-04-09T23:30:38Z
publishDate 2023-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-50f493ab13384f5998b77c96ed7e0a262023-03-21T05:31:43ZengPublic Library of Science (PLoS)PLoS ONE1932-62032023-01-01181e027949110.1371/journal.pone.0279491First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia.Aaron D PanBonnie F JacobsRosemary T BushManuel de la EstrellaFriðgeir GrímssonPatrick S HerendeenXander M van der BurgtEllen D CurranoMany tropical wet forests are species-rich and have relatively even species frequency distributions. But, dominance by a single canopy species can also occur in tropical wet climates and can remain stable for centuries. These are uncommon globally, with the African wet tropics supporting more such communities than the Neotropics or Southeast Asia. Differences in regional evolutionary histories are implied by biogeography: most of Africa's monodominance-forming species are Amherstieae-tribe legumes; monodominance in Neotropical forests occur among diverse taxonomic groups, often legumes, but rarely Amherstieae, and monodominance in Southeast Asian forests occurs mostly among Dipterocarpaceae species. African monodominant forests have been characterized ecologically and taxonomically, but their deep-time history is unknown despite their significant presence and bottom-up ecological influence on diversity. Herein we describe fossil leaflets of Englerodendron mulugetanum sp. nov., an extinct species of the extant genus Englerodendron (Berlinia Clade, Amherstieae, Detarioideae) from the 21.73 Ma Mush Valley site in Ethiopia. We also document a detailed study of associated legume pollen, which originate from a single taxon sharing characters with more than one extant descendant. Taxonomically, the pollen is most comparable to that from some extant Englerodendron species and supports a likely affiliation with the Englerodendron macrofossils. The Mush Valley site provides the first fossil evidence of a monodominant tropical forest in Africa as represented by leaflets and pollen. Previous studies documented >2400 leaves and leaflets from localities at six stratigraphic levels spanning 50,000-60,000 years of nearly continuous deposition within seven meters of section; all but the basal level contain ≥ 50% E. mulugetanum leaflets. Modern leaf litter studies in African mixed vs. monodominant forests indicates the likelihood of monodominance in the forests that surrounded the Mush paleolake, particularly after the basal level. Thus, we provide an early case for monodominance within the Amherstieae legumes in Africa.https://doi.org/10.1371/journal.pone.0279491
spellingShingle Aaron D Pan
Bonnie F Jacobs
Rosemary T Bush
Manuel de la Estrella
Friðgeir Grímsson
Patrick S Herendeen
Xander M van der Burgt
Ellen D Currano
First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia.
PLoS ONE
title First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia.
title_full First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia.
title_fullStr First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia.
title_full_unstemmed First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia.
title_short First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia.
title_sort first evidence of a monodominant englerodendron amherstieae detarioideae leguminosae tropical moist forest from the early miocene 21 73 ma of ethiopia
url https://doi.org/10.1371/journal.pone.0279491
work_keys_str_mv AT aarondpan firstevidenceofamonodominantenglerodendronamherstieaedetarioideaeleguminosaetropicalmoistforestfromtheearlymiocene2173maofethiopia
AT bonniefjacobs firstevidenceofamonodominantenglerodendronamherstieaedetarioideaeleguminosaetropicalmoistforestfromtheearlymiocene2173maofethiopia
AT rosemarytbush firstevidenceofamonodominantenglerodendronamherstieaedetarioideaeleguminosaetropicalmoistforestfromtheearlymiocene2173maofethiopia
AT manueldelaestrella firstevidenceofamonodominantenglerodendronamherstieaedetarioideaeleguminosaetropicalmoistforestfromtheearlymiocene2173maofethiopia
AT friðgeirgrimsson firstevidenceofamonodominantenglerodendronamherstieaedetarioideaeleguminosaetropicalmoistforestfromtheearlymiocene2173maofethiopia
AT patricksherendeen firstevidenceofamonodominantenglerodendronamherstieaedetarioideaeleguminosaetropicalmoistforestfromtheearlymiocene2173maofethiopia
AT xandermvanderburgt firstevidenceofamonodominantenglerodendronamherstieaedetarioideaeleguminosaetropicalmoistforestfromtheearlymiocene2173maofethiopia
AT ellendcurrano firstevidenceofamonodominantenglerodendronamherstieaedetarioideaeleguminosaetropicalmoistforestfromtheearlymiocene2173maofethiopia