Palms can do much more
than sway on beaches of pure white sand.
According to new research from Aarhus University,
they can predict the future by telling the
story of how flora and fauna have been affected
by climate change for millions of years.
2012.04.24 | Peter Bondo
Christensen - The changes in tropical rainforest
area over the last 55 million years differ
between South America and Africa. (A) In
South America, there was a suitable warm-wet
climate and a constant presence of large
rainforest areas. (B) In Africa, strong
losses of tropical rainforests have occurred,
especially over the last 10 million years
due to climate change (massive drying).
Source: modified from Kissling et al. (2012),
PNAS in press.
Tropical areas provide
similar conditions with high temperatures
and humidity regardless of whether you are
in Asia, Africa or South America. And you
can find lush rainforests in all these places.
However, tropical rainforests are not the
same. There are fundamental differences
in the species composition in the rainforests
on the different continents.
Scientists at Aarhus University have spearheaded
research results that shed new light on
the processes forming the composition of
species assemblages in the tropics. There
are actually more than 2400 species of palms
and, by studying them, the researchers have
shown that the palm assemblages we find
in the tropics today are to a large extent
formed by climatic changes of the past,
taking place over millions of years.
“It comes as a surprise to us that climate
change over millions of years still leaves
a signature in the composition of species
assemblages we see today. If species are
severely affected by current and future
climate change, it’ll mean that there are
long-lasting consequences for biodiversity,
maybe over many millions of years to come
– at least much longer than we’ve ever dreamt
of before,” says Daniel Kissling, who initiated
the ground-breaking research results shortly
to be published in the prestigious journal
Proceedings of the National Academy of Sciences
of the USA (PNAS).
South America has had a relatively stable
humid and warm climate for the last 50 million
years, and rainforests have been widespread
throughout this entire period. This is where
species diversity is highest. There have
been good living conditions and plenty of
space for many new species to arise. As
species formation has been concentrated
in particular groups, the species-rich South
American palm communities are now dominated
by closely related species.
Africa, on the other hand, has been hit
by severe drying during the last 10 to 30
million years. The area of rainforest has
thus diminished dramatically, until it reached
a minimum during the cold, dry ice ages
that have repeatedly affected the world
over and over again during the last 3 million
years. As a result of past climatic changes,
many species have simply disappeared entirely
from the continent. There are therefore
far fewer palm species in Africa than in
South America. The poor palm flora of Africa
thus has a relict character, and consists
of species that are often not closely related
to each other.
Working partners
Ecoinformatics & Biodiversity Group,
Department of Bioscience, Aarhus University
The research was led and predominantly conducted
at the Ecoinformatics & Biodiversity
(ECOINF) Group at Aarhus University. The
research group focuses on using the rapid
increases in data sources and computing
and statistical modelling capabilities to
advance biodiversity science, ecology, and
environmental science. In addition, a long
tradition of palm research exists in this
group, with world-leading expertise on all
aspects of the biology of palms.
Authors from ECOINF: W. Daniel Kissling,
Wolf L. Eiserhardt, Finn Borchsenius, Henrik
Balslev, and Jens-Christian Svenning
Royal Botanic Gardens, Kew, UK
The Royal Botanic Gardens, Kew, is a world-famous
botanical institution, internationally respected
for its outstanding living collection of
plants and world-class herbarium, as well
as its scientific expertise in plant diversity,
conservation and sustainable development
in the UK and around the world. Kew Gardens
is a major international visitor attraction
that, with its country estate Wakehurst
Place, attracts nearly two million visitors
every year. Kew was made a UNESCO World
Heritage Site in July 2003 and celebrated
its 250th anniversary in 2009.
Author: William J. Baker, Head of Palm Research
Institut de Recherche pour le Développement
(IRD), Montpellier, France
The IRD is a unique European research institution
with a focus on conducting research in the
southern hemisphere. Its researchers work
on issues of major global importance such
as global warming, biodiversity, and poverty.
Palm research focuses on systematics and
biogeography, and the evolution of tropical
rainforests.
Author: Thomas L. P. Couvreur
Methods
Our research uses an informatics approach
to ecology and evolution by handling and
analysing large datasets, including databases
on the distribution of thousands of species
across the world, global data layers on
paleo-reconstructions of climate and tropical
rainforests, and molecular information on
the phylogenetic tree of palms. By doing
this, we build on major recent advances
in ecology, informatics, systematic botany,
and paleo-geography.
