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The distributions of many terrestrial organisms are currently shifting in latitude or elevation in response to changing climate. Using a meta-analysis, we estimated that the distributions of species have recently shifted to higher elevations at a median rate of 11.0 meters per decade, and to higher latitudes at a median rate of 16.9 kilometers per decade. These rates are approximately two and three times faster than previously reported. The distances moved by species are greatest in studies showing the highest levels of warming, with average latitudinal shifts being generally sufficient to track temperature changes. However, individual species vary greatly in their rates of change, suggesting that the range shift of each species depends on multiple internal species traits and external drivers of change. Rapid average shifts derive from a wide diversity of responses by individual species.
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Acknowledgments: This work was supported by the Howard
Hughes Medical Institute (C.B.L., S.R.S., D.M.K., D.H.),
the NSF (CAREER-0644282 to M.K., DBI-0644111 to
A.S.), the NIH (R01-HG004037 to M.K., P50- HG02568
to D.M.K., U54-HG003067 to K.L-T., 1U01-HG004695
to C.B.L., 5P41-HG002371to B.J.R.), the Sloan
Foundation (M.K.), and the European Science Foundation
(EURYI to K.L-T.).
Supporting Online Material
Materials and Methods
Figs. S1 to S9
Tables S1 to S12
References (2949)
10 January 2011; accepted 24 June 2011
Rapid Range Shifts of Species
Associated with High Levels
of Climate Warming
I-Ching Chen,
Jane K. Hill,
Ralf Ohlemüller,
David B. Roy,
Chris D. Thomas
The distributions of many terrestrial organisms are currently shifting in latitude or elevation in response
to changing climate. Using a meta-analysis, we estimated that the distributions of species have
recently shifted to higher elevations at a median rate of 11.0 meters per decade, and to higher latitudes
at a median rate of 16.9 kilometers per decade. These rates are approximately two and three times
faster than previously reported. The distances moved by species are greatest in studies showing the
highest levels of warming, with average latitudinal shifts being generally sufficient to track temperature
changes. However, individual species vary greatly in their rates of change, suggesting that the
range shift of each species depends on multiple internal species traits and external drivers of change.
Rapid average shifts derive from a wide diversity of responses by individual species.
Threats to global biodiversity from climate
change (1-8) make it important to identify
the rates at which species have already
responded to recent warming. There is strong evi-
dence that species have changed the timing of
their life cycles during the year and that this is
linked to annual and longer-term variations in
temperature (912). Many species have also
shifted their geographic distributions toward
higher latitudes and elevations (1317), but this
evidence has previously fallen short of demon-
strating a direct link between temperature change
and range shifts; that is, greater range shifts have
not been demonstrated for regions with the high-
est levels of warming.
We undertook a meta-analysis of available
studies of latitudinal (Europe, North America,
and Chile) and elevational (Europe, North Amer-
ica, Malaysia, and Marion Island) range shifts for
a range of taxonomic groups (18)(tableS1).We
considered N= 23 taxonomic group × geographic
region combinations for latitude, incorporating
764 individual species responses, and N=31
taxonomic group × region combinations for ele-
vation, representing 1367 species responses. For
the purpose of analysis, the mean shift across all
species of a given taxonomic group, in a given
region, was taken to represent a single value (for
example, plants in Switzerland or birds in New
York State; table S1) (18).
The latitudinal analysis revealed that spe-
cies have moved away from the Equator at a
median rate of 16.9 km decade
(mean = 17.6
km decade
, SE = 2.9, N= 22 species group ×
region combinations, one-sample ttest versus
zero shift, t= 6.10, P< 0.0001). Weighting each
study by the (numberofspecies)inthegrou
region combination gave a mean rate of 16.6 km
. For elevation, there was a median shift
to higher elevations of 11.0 m uphill decade
(mean = 12.2 m decade
, SE = 1.8, N=30spe-
cies groups × regions, one-sample ttest versus
zero shift, t= 7.04, P< 0.0001). Weighting ele-
vation studies by (number of species) gave a
mean rate of uphill movement of 11.1 m decade
A previous meta-analysis (14)ofdistribu-
tion changes analyzed individual species, rather
than the averages of taxonomic groups × regions
that we used, and also included data on latitu-
dinal and elevational shifts in the same analysis
(18). It concluded that ranges had shifted toward
higher latitudes at 6.1 km decade
er elevations at 6.1 m decade
(14), whereas
the rates of range shift that we found were sig-
nificantly greater [N= 22 species groups × regions,
one-sample ttest versus 6.1 km decade
3.99, P= 0.0007 for latitude; N= 30 groups ×
regions, one-sample ttest versus 6.1 m decade
t= 3.49, P= 0.002 for elevation (18)]. Our
estimated mean rates are approximately three
and two times higher than those in (14), for
Department of Biology, University of York, Wentworth Way,
York YO10 5DD, UK.
Biodiversity Research Center, Academia
Sinica, 128 Academia Road, Section 2, Nankang Taipei 115,
School of Biological and Biomedical Sciences, and
Institute of Hazard, Risk and Resilience, Durham University,
South Road, Durham DH1 3LE, UK.
Centre for Ecology &
Hydrology, Crowmarsh Gifford, Wallingford, Oxfordshire,
OX10 8BB, UK.
*To whom correspondence should be addressed. E-mail:
Fig. 1. Relationship between observed and expected range shifts in response to climate change, for (A)
latitude and (B) elevation. Points represent the mean responses (TSE)ofspeciesinaparticulartax-
onomic group, in a given region. Positive values indicate shifts toward the pole and to higher ele-
vations. Diagonals represent 1:1 lines, where expected and observed responses are equal. Open circles,
birds; open triangles, mammals; solid circles, arthropods; solid inverted triangles, plants; solid square,
herptiles; solid diamond, fish; solid triangle, mollusks.
on August 18, 2011www.sciencemag.orgDownloaded from
latitude and elevation respectively, implying much
greater responses of species to climate warming
than previously reported (18). Most of the data
we analyzed are from the temperate zone and
from tropical mountains (table S1), where eco-
systems are at least partly temperature-limited;
different rates of change might be observed in
moisture-limited ecosystems (19).
Published studies have shown nonrandom
latitudinal and elevational changes (1, 7, 1317)
but have not previously demonstrated a statis-
tical linkage between range shifts and levels
of warming. We found that observed latitudinal
and elevational shifts (the latter more weakly)
have been significantly greater in studies with
higher levels of warming (mean latitudinal shift
versus average temperature increase; N=23spe-
cies groups × regions, Pearson correlation coef-
ficient (r) = 0.59, P= 0.003; mean elevational
shift versus temperature increase; N= 31, r=
0.37, P= 0.042). Temperature gradients differ
across the world, so a given level of warming
leads to different expected range shifts of spe-
cies in different regions (20), assuming that spe-
cies track climate changes. To estimate the
expected shifts, we calculated the distances in
latitude (kilometers) and elevation (meters) that
species in a given region would have been re-
quired to move to track temperature changes
and thus to experience the same average tem-
perature at the end of the recording period as
encountered at the start (18) (table S1). We
found that both observed latitudinal and ele-
vation range shifts were correlated with predicted
distances (Fig. 1A, N= 20 species groups ×
regions, r= 0.65, P= 0.002 for latitude; Fig.
1B, N= 30 groups × regions, r= 0.39, P=
0.035 for elevation), so our analyses directly
link terrestrial range shifts to regional and study
differences in the warming experienced.
Despite reports that many species lag behind
climate change (2123), nearly as many studies
of observed latitudinal changes fall above as
below the observed = expected line in Fig. 1A
(9 points above, 11 below; c
= 0.20, 1 df, P=
0.65), suggesting that mean latitudinal shifts are
not consistently lagging behind the climate. The
lag in elevation response (Fig. 1B; 2 points above
the 1:1 line, 28 below; c
= 22.53, 1 df, P<
0.001) is equally surprising because the required
distances to track climate are much shorter than
for latitudinal shifts (20). Real and apparent ele-
vation lags may arise if suitable new conditions
at higher elevations occur only in locations that
cannot be reached easily (for example, on other
mountain peaks), or they may reflect the topo-
graphic and microclimatic complexity of moun-
tainous terrain [for example, cooler locations
may be on poleward-facing slopes rather than
higher (24)]; the need for finer-resolution analy-
ses (25); and additional topographic, climatic, ge-
ological, and ecological constraints [for example,
causing declines in cloud forest species (2628)].
Taxonomic differences are not consistent pre-
dictors of recent response rates. For example,
birds seem to have responded least in terms of
elevational shifts but had a slightly greater than
expected latitudinal shift (Fig. 1). Much greater
variation is associated with differences among
species within a taxonomic group than between
taxonomic groups (Fig. 2 and table S2). For lat-
itudinal studies, on average 22% (average of
N= 23 species groups × regions) of the species
actually shifted in the opposite direction to that
expected. Similarly, 25% of species shifted down-
hill rather than to higher elevations (average of
N= 29 species groups × regions). Thus, despite
an overall significant shift toward higher lati-
tudes and elevations, which is greatest where
the climate has warmed the most, and despite
around three-quarters of species shifting pole-
ward and to higher elevations, we found that
species have exhibited a high diversity of range
shifts in recent decades.
At least three processes are likely to generate
the high diversity of range shifts among species:
time delays in speciesresponses, individualistic
physiological constraints, and alternative and in-
teracting drivers of change. Species may lag be-
hind climate change if they are habitat specialists
or immobile species that cannot colonize across
fragmented landscapes (17,2123), or if they
possess other traits associated with low extinc-
tion or colonization rates (29). Species may also
show individualistic physiological responses to
different aspects of the climate, such as different
sensitivities to maximum and minimum temper-
atures at critical times of their life cycles. These
sensitivities will combine with variable wait times
for different novel climatic extremes to take
place (30). Species are also affected to dif-
ferent extents by nonclimatic factors and by
multispecies interactions, which themselves de-
pend on a diversity of environmental drivers
(21,28). For example, a species might retreat
toward the Equator at its poleward margin if it
contracts with habitat loss faster than it expands
through climate warming; whereas the poleward
range margin of a species that thrives in novel ag-
ricultural landscapes may spread at a rate exceed-
ing that expected, were warming the sole driver.
We found that rates of latitudinal and eleva-
tional shifts are substantially greater than reported
Fig. 2. Observed latitudinal shifts of the northern range boundaries of species within four exemplar
taxonomic groups, studied over 25 years in Britain. (A) Spiders (85 species), (B)groundbeetles
(59 species), (C) butterflies (29 species), and (D) grasshoppers and allies (22 species). Positive
latitudinal shifts indicate movement toward the north (pole); negative values indicate shifts toward the
south (Equator). The solid line shows zero shift, the short-dashed line indicates the median observed
shift, and the long-dashed line indicates the predicted range shift. SCIENCE VOL 333 19 AUGUST 2011 1025
on August 18, 2011www.sciencemag.orgDownloaded from
in a previous meta-analysis, and increase with
the level of warming. We conclude that average
rates of latitudinal distribution change match
those expected on the basis of average temper-
ature change, but that variation is so great within
taxonomic groups that more detailed physio-
logical, ecological and environmental data are
required to provide specific prognoses for indi-
vidual species.
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Acknowledgments: We thank A. Bergamini, R. Hickling,
R. Wilson, and B. Zuckerberg for data; H.-J. Shiu for
statistical assistance; S.-F. Shen, the Ministry of Education
in Taiwan, a UK Overseas Research Scholarship Award,
and the Natural Environment Research Council for
support; and anonymous referees for comments on the
manuscript. We are particularly grateful to the many
thousands of volunteers responsible for collecting most of
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in the supporting online material.
Supporting Online Material
Materials and Methods
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Aneuploidy Drives Genomic
Instability in Yeast
Jason M. Sheltzer,
Heidi M. Blank,
Sarah J. Pfau,
Yoshie Tange,
Benson M. George,
Timothy J. Humpton,
Ilana L. Brito,
Yasushi Hiraoka,
Osami Niwa,
Angelika Amon
Aneuploidy decreases cellular fitness, yet it is also associated with cancer, a disease of enhanced
proliferative capacity. To investigate one mechanism by which aneuploidy could contribute to
tumorigenesis, we examined the effects of aneuploidy on genomic stability. We analyzed 13 budding
yeast strains that carry extra copies of single chromosomes and found that all aneuploid strains
exhibited one or more forms of genomic instability. Most strains displayed increased chromosome loss
and mitotic recombination, as well as defective DNA damage repair. Aneuploid fission yeast strains
also exhibited defects in mitotic recombination. Aneuploidy-induced genomic instability could facilitate
the development of genetic alterations that drive malignant growth in cancer.
Whole-chromosome aneuploidyor a
karyotype that is not a multiple of the
haploid complementis found in great-
er than 90% of human tumors and may contrib-
ute to cancer development (1,2). It has been
suggested that aneuploidy increases genomic
instability, which could accelerate the acquisition
of growth-promoting genetic alterations (1,3).
However, whereas aneuploidy is a result of ge-
nomic instability, there is at present limited evi-
dence as to whether genomic instability can be a
consequence of aneuploidy itself. To test this
possibility directly, we assayed chromosome seg-
regation fidelity in 13 haploid strains of Saccha-
romyces cerevisiae that carry additional copies
of single yeast chromosomes (4). These aneu-
ploid strains (henceforth disomes) display im-
paired proliferation and sensitivity to conditions
that interfere with protein homeostasis (4,5).
We measured the segregation fidelity of a yeast
artificial chromosome (YAC) containing human
DNA and found that the rate of chromosome
missegregation was increased in 9 out of 13 di-
somic strains relative to a euploid control (Fig.
1A). The increase ranged from 1.7-fold to 3.3-
fold, comparable to the fold increase observed
in strains lacking the kinetochore components
Chl4 or Mcm21. Consistent with chromosome
segregation defects, 8 out of 13 disomic strains
displayed impaired proliferation on plates con-
taining the microtubule poison benomyl, includ-
ing a majority of the strains that had increased
rates of YAC loss (Fig. 1B).
Chromosome missegregation can result from
defects in chromosome attachment to the mitotic
spindle or from problems in DNA replication or
repair. Defects in any of these processes delay
mitosis by stabilizing the anaphase inhibitor
Pds1 (securin) (6). Five out of five disomes (di-
somes V, VIII, XI, XV, and XVI) exhibited de-
layed degradation of Pds1 relative to wild type
after release from a pheromone-induced G
(Fig. 1C and fig. S1). Defective chromosome bi-
orientation delays anaphase through the mitotic
checkpoint component Mad2 (6). Deletion of
MAD2 had no effect on Pds1 persistence in four
disomes, but eliminated this persistence in disome
V cells (fig. S1). Disome V also delayed Pds1 deg-
radation after release from a mitotic arrest in-
duced by the microtubule poison nocodazole,
which demonstrated that this strain exhibits a bi-
orientation defect. Disome XVI, which displayed
Mad2-independent stabilization of Pds1, recov-
ered from nocodazole with wild-type kinetics (fig.
S2). Thus, Pds1 persistence results predominant-
ly from Mad2-independent defects in genome
replication and/or repair (see below).
We next investigated whether aneuploidy
could affect the rate of forward mutation. Di-
somes V, VIII, X, and XIV displayed an in-
creased mutation rate at two independent loci,
whereas disome IV displayed an increased
mutation rate at CAN1 but not at URA3 (Fig.
2A). The fold increase ranged from 2.2-fold to
7.1-fold, less than the 9.5-fold and 12-fold in-
creases observed in a recombination-deficient
rad51Dmutant and a mismatch repairdeficient
msh2Dmutant, respectively. Additionally, in an as-
say for microsatellite instability, we found that di-
somes VIII and XVI displayed increased instability
in a poly(GT) tract (fig. S3), which demonstrated
that aneuploidy can enhance both simple se-
quence instability and forward mutagenesis.
To define the mechanism underlying the
increased mutation rate in aneuploid cells, we
David H. Koch Institute for Integrative Cancer Research and
Howard Hughes Medical Institute (HHMI), Massachusetts In-
stitute of Technology, Cambridge, MA 02139, USA.
School of Frontier Biosciences, Osaka University 1-3 Yamadaoka,
Suita 565-0871, Japan.
Department of Ecology, Evolution and
Environmental Biology, Columbia University, New York, NY
10027, USA.
Kobe Advanced ICT Research Center, National Insti-
tute of Information and Communications Technology 588-2 Iwaoka,
Iwaoka-cho, Nishi-ku, Kobe 651-2492, Japan.
The Rockefeller
University, 1230 York Avenue, New York, NY 10065, USA.
*To whom correspondence should be addressed. E-mail:
19 AUGUST 2011 VOL 333 SCIENCE www.sciencemag.org1026
on August 18, 2011www.sciencemag.orgDownloaded from
... Thus, for wider temperature gradients, such as in mountainous areas where temperature decreases at higher altitudes, the thermal range for species performance and distribution would be subject to an increase in temperature [57]. Whereas an increase of 2-3 • C is believed to drive many species out of their thermal range and to extinction in the current projections of global temperature increase [57][58][59]. Therefore, the suggested sensitivity of maximum canopy height variation to temperature changes could play a significant role in understanding and monitoring forest responses to climatic changes. ...
... Similarly, dispersal can promote the recovery of natural systems and gene flow in anthropogenically disturbed landscapes (Wunderle Jr, 1997;Bacles, Lowe & Ennos, 2003;Lenz et al., 2011; but see Duncan & Chapman, 1999). In some scenarios, animals can even facilitate plant establishment by moving propagules sufficient distances to track climate change (Chen et al., 2011;Coutts et al., 2011;Bellard et al., 2012;Pardi & Smith, 2012;Corlett & Westcott, 2013;Mokany, Prasad & Westcott, 2014;Naoe et al., 2016;Gonz alez-Varo, L opez-Bao & Guiti an, 2017). On the other hand, habitat loss and extirpation, among other factors, threaten many dispersal relationships (Emer et al., 2020). ...
Conceptual gaps and imprecise terms and definitions may obscure the breadth of plant–animal dispersal relationships involved in directed dispersal. The term ‘directed’ indicates predictable delivery to favourable microsites. However, directed dispersal was initially considered uncommon in diffuse mutualisms (i.e. those involving many species), partly because plants rarely influence post‐removal propagule fate without specialized adaptations. This rationale implies that donor plants play an active role in directed dispersal by manipulating vector behaviour after propagule removal. However, even in most classic examples of directed dispersal, participating plants do not influence animal behaviour after propagule removal. Instead, such plants may take advantage of vector attraction to favourable plant microsites, indicating a need to expand upon current interpretations of directed dispersal. We contend that directed dispersal can emerge whenever propagules are disproportionately delivered to favourable microsites as a result of predictably skewed vector behaviour. Thus, we propose distinguishing active and passive forms of directed dispersal. In active directed dispersal, the donor plant achieves disproportionate arrival to favourable microsites by influencing vector behaviour after propagule removal. By contrast, passive directed dispersal occurs when the donor plant takes advantage of vector behaviour to arrive at favourable microsites. Whereas predictable post‐removal vector behaviour is dictated by characteristics of the donor plant in active directed dispersal, characteristics of the destination dictate predictable post‐removal vector behaviour in passive directed dispersal. Importantly, this passive form of directed dispersal may emerge in more plant–animal dispersal relationships because specialized adaptations in donor plants that influence post‐removal vector behaviour are not required. We explore the occurrence and consequences of passive directed dispersal using the unifying generalized gravity model of dispersal. This model successfully describes vectored dispersal by incorporating the influence of the environment (i.e. attractiveness of microsites) on vector movement. When applying gravity models to dispersal, the three components of Newton's gravity equation (i.e. gravitational force, object mass, and distance between centres of mass) become analogous to propagules moving towards a location based on characteristics of the donor plant, the destination, and relocation processes. The generalized gravity model predicts passive directed dispersal in plant–animal dispersal relationships when (i) animal vectors are predictably attracted to specific destinations, (ii) animal vectors disproportionately disperse propagules to those destinations, and (iii) those destinations are also favourable microsites for the dispersed plants. Our literature search produced evidence for these three conditions broadly, and we identified 13 distinct scenarios where passive directed dispersal likely occurs because vector behaviour is predictably skewed towards favourable microsites. We discuss the wide applicability of passive directed dispersal to plant–animal mutualisms and provide new insights into the vulnerability of those mutualisms to global change.
... While alien species have been un-/ intentionally moved by humans into areas in which they did not naturally occur (e.g., through the introduction of propagules, Richardson et al., 2000), neonative species have expanded their range via natural dispersal in response to anthropogenic environmental changes (Essl et al., 2019). As the phenomenon of species that expand their ranges seems to be increasing (Lenoir & Svenning, 2015;Steinbauer et al., 2018) and is undisputed (Chen et al., 2011;Poloczanska et al., 2013;Thomas, 2010), it has still to be determined to which degree neonative species impact their novel, recipient ecosystems in comparison with alien species. Some authors have argued that the impacts of native species can sometimes be as severe as those of alien species (Canavan et al., 2019;Davis et al., 2011;Nackley et al., 2017), and it is unclear whether similar considerations apply to neonative species. ...
Full-text available
Anthropogenic environmental modifications such as climate or land‐use change are causing species to move on their own beyond their native ranges. As this phenomenon will increase in the near future, it is crucial to determine whether range‐expanding species, or neonatives, are more or less likely than native and alien species to impact their recipient ecosystems. Here, we compared impact magnitudes of bark beetle species from their native, neonative and alien ranges, simultaneously. Global. We formulated four general scenarios about the magnitude of environmental impacts in different ranges (native, neonative and alien) based on hypotheses commonly used in invasion biology. We tested these scenarios globally on Dendroctonus bark beetles, asking whether they have the most harmful impacts in their native, neonative or alien ranges. Impacts reported in the literature were assessed with the IUCN Environmental Impact Classification for Alien Taxa (EICAT). We found that bark beetles cause the most harmful impacts in their native ranges, followed by the neonative ranges, while impacts in their alien ranges are the lowest. This indicates that the more dissimilar the environment is from that in the native range, the lower the probability of high‐impact magnitudes. Our results align with several non‐exclusive hypotheses, e.g. pre‐adaptation and habitat filtering, while they do not support others, e.g. enemy release or Darwin’s naturalization. The results are also in contrast with previous studies on vertebrates and plants, which found no or mixed differences in impact magnitudes with biogeographic origin. Our analysis suggests that bark beetles, like other species that are keystone and abundant in their native ranges, have generally lower impacts when introduced to novel environments due to biotic resistance or lack of pre‐adaptation. Research and management implications regarding the impacts of neonative and alien populations are also discussed.
... To design effective conservation and management strategies and mitigation measures to climate change, we need a holistic understanding of the ecological, physiological, genetic, and biogeographical mechanisms driving species responses to climate change (Bonebrake et al. 2018). Ongoing responses to climate change are already visible among many taxa, where a growing body of research has shown that species respond to climate-driven changes in their climatic niche in multiple ways (Both et al. 2006;Chen et al. 2011;Bellard et al. 2012;Stephens et al. 2016;Ryding et al. 2021). ...
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Climatic warming is forcing species to shift their ranges poleward, which has been demonstrated for many taxa globally. Yet, the influence of habitat types on within- and among-species variations of distribution shifts has rarely been studied, especially during the non-breeding season. Here, we investigated habitat-specific shift distances of northern range margins and directions of the distribution center based on long-term data of overwintering birds in Finland. Specifically, we explored influences of habitat type, species’ snow depth tolerance, species’ climatic niche and habitat specialization on range shifts during the past 40 years in 81 bird species. Birds overwintering in arable land shifted more clearly toward north compared to birds of the same species in rural and forest habitats, while the northern range margin shift distances did not significantly differ among the habitat types. Range shifts were more linked with the species’ snow depth tolerance rather than species’ climatic niche. Snow depth tolerance of species was negatively associated with the eastward shift direction across all habitats, while we found habitat-specific patterns with snow depth for northward shift directions and northern margin shift distances. Species with stronger habitat specializations shifted more strongly toward north as compared to generalist species, whereas the climatic niche of bird species only marginally correlated with range shifts, so that cold-dwelling species shifted longer distances and more clearly eastward. Our study reveals habitat-specific patterns linked to snow conditions for overwintering boreal birds and highlights the importance of habitat availability and preference in climate driven range shifts.
... While the areas with high species gain offer opportunities for ex-situ conservation of THPs, such as the central Himalayas Mountains, southeast Xizang (hotspot 7), north Guangxi and south Guizhou (hotspot 10), southwest Guangxi (east part of hotspot 14). In addition, climate change also poses a huge challenge to the current static conservation network (Chen et al., 2011;Zomer et al., 2015). For nature reserves facing dramatic climate change, the range dynamics change of species in these nature reserves should be monitored, and it is necessary to consider climate change as an important factor in setting the boundaries of nature reserves and protection strategies in the future. ...
A significant fraction of higher plants in China are threatened due to dramatic landscape transformation and increasing climate change. However, the conservation effectiveness of threatened higher plants (THPs) and their response to climate change are still underexplored to date. Based on the latest list of THPs in China, we obtained 102,593 occurrence records with latitude and longitude for 3,858 THPs. By integrating the distribution patterns of three biodiversity indexes (i.e. species richness, species complementarity and weighted endemism) and ten plant categories, we identified hotspots for THPs and calculated the conservation effectiveness of nature reserves. Then, 1959 THPs were selected to project the shift of species richness and range sizes under climate change (RCP 2.6 and RCP 8.5). In total, 16 hotspot areas covering 7.38% of Chinese land area and containing 91.73% of THPs were identified. Current nature reserves protected 35.05% of hotspots, 73.07% of all THPs and 56.64% of narrow‐ranged species. By the 2070s, the species richness of THPs were predicted to decrease in Southeast and Central China, and 42.42% (RCP 2.6) and 51.40% (RCP 8.5) of the 1959 THPs would confront habitat contraction. Future conservation efforts should focus on the conservation gaps and carry out targeted conservation for THPs with narrow distribution range. In order to cope with climate change, the hotspots with relatively low species loss can serve as important areas to contain current species diversity and the areas with high species gain offer opportunities for ex‐situ conservation of THPs. This article is protected by copyright. All rights reserved.
... Since the early 19th century, overwhelming scientific evidence has shown that the global climate is changing rapidly, and it is adversely affecting species and ecosystems. In general, species' climate suitabilities are moving northwards and upwards respectively (Chen et al., 2011). These shifts are associated with climate-induced changes in the location of physiologically optimal and tolerable temperatures (Pörtner, 2001), the availability and abundance of food and habitats (Mantyka-Pringle et al. 2012), interspecific interactions (Suttle et al., 2007), the timing of seasonal life-history events such as migration, blooming, and reproduction (Post et al., 2001), and the rate of species extinctions (Cahill et al., 2013). ...
Global climate change has become a major threat to biodiversity, posing severe challenges to species conservation. This is particularly true for species such as Horsfieldia tetratepala that have extremely small populations in the wild. Little is known about the species distribution of H. tetratepala in the current climate, as well as how that will change with potential future climates. The key environmental factors that influence its expansion, especially its habitat sustainability and its potential to adapt to climate change, are also unknown, though such information is vital for the protection of this endangered species. Based on six climate factors and 25 species distribution points, this study used the maximum entropy model (MaxEnt) to simulate the potential distribution for H. tetratepala in three periods (current, 2050s, and 2070s), and to investigate the changes in distribution patterns and the main environmental factors affecting species distribution. The modeling results show that the most important bioclimatic variables affecting H. tetratepala were precipitation of the warmest quarter (Bio_18) and temperature seasonality (Bio_4). The suitable areas for H. tetratepala will gradually be lost in Yunnan but will be generally offset in the northeastward direction, expanding in Hainan, Guangzhou, and Taiwan provinces under the future climate conditions. Therefore, we recommend protecting the habitats of H. tetratepala in Yunnan and strengthening the in-depth species investigation and monitoring in areas (Hainan, Guangzhou, and Taiwan) where no related reports of H. tetratepala have been reported. The results improve our understanding of this species’ response under the changing climate and benefit strategies for its conservation.
Studying wildlife–habitat relationships at the edges of their range can provide valuable insights into the environmental factors limiting wildlife distributions and most likely to drive extirpations and range shifts in response to landscape change. Yet the relative impact of those factors is likely different along the range margin, so it is important to identify the limitations to suitable habitat at both regional and local scales. Some of the most drastic impacts of large‐scale landscape changes in North America have occurred and are forecasted in the sagebrush steppe ecosystems, where species unable to seek new habitat in the fragmented landscape will be vulnerable to climatic extremes, vegetation community shifts, and anthropogenic land use change. One of the species likely under major threat from landscape changes is the greater sage‐grouse (Centrocercus urophasianus), a sagebrush obligate with habitat constraints that make it susceptible to habitat loss impacts as sagebrush systems contract and fragment at their southern range margin, already naturally fragmented. In this study, we evaluated factors of topography and land cover directly impacting habitat selection by sage‐grouse in four study areas along their lagging range edge. We used >116,000 GPS locations from >90 grouse across four study areas in southern Utah and Nevada from 2014 to 2020 in habitat selection analyses using random forest models. Our results showed that sage‐grouse exploit topography and sagebrush cover, possibly to break predator sight lines and moderate the risk posed by avian predators using tree perches, complicating the effects of tree cover and conifer encroachment into sagebrush habitat. We found similar trends across all four study areas, suggesting sage‐grouse along the southern range margin face similar limitations. However, the effects were nonlinear and varied—models trained in one study area were only moderately successful at predicting selection in others. The local idiosyncrasies along this southern range margin indicate a need for place‐based conservation for sage‐grouse and other potentially imperiled species. Incorporating new understandings of local impacts will refine regional and range‐wide models and support efforts to effectively create habitat and plan for range shifts by vulnerable species in response to environmental change.
The ongoing climate crisis is a significant threat to global biodiversity. As Earth warms, many species respond by shifting their geographical ranges either polewards, or in mountainous regions, upslope towards higher elevations, presumably to track suitable thermal environments. Upslope range shifts are of particular concern in tropical mountain ranges because: (a) tropical species are particularly thermally sensitive; (b) species moving upwards could become locally extirpated as they run out of habitable space; and (c) tropical mountains harbor a high fraction of Earth's terrestrial biodiversity. Rapid upslope shifts can, therefore, result in significant biodiversity losses. We used community science data over a 13‐year period to evaluate whether 93 Eastern Himalayan bird species might be shifting to higher elevations. To do this, we analyzed changes in their occurrence probabilities in eBird checklists from birdwatching hotspots at fixed elevations. We found patterns consistent with upslope range shifts; species with elevational ranges primarily below hotspot elevations show increases in their occurrence probability over time, and those with most of their elevational ranges above a hotspot elevation decline in occurrence probability. Our findings are suggestive of rapid responses to climate change by Eastern Himalayan birds. We caution that Eastern Himalayan bird species might be at special risk from increasing global temperatures because of heightened thermal sensitivity coupled with high rates of warming in the region. To remain resilient in the face of climate change, Eastern Himalayan birds likely require undisturbed habitats spanning entire elevational gradients, to track rising temperatures by moving to higher elevations. Montane species are expected to shift their elevational ranges upslope in response to global warming. Using 13 years of community science data on birds from two birding hotspots in the Eastern Himalayas, we analyzed changes in the probability of occurrence for 93 species. Trends from community science data are indicative of upslope range shifts in Eastern Himalayan birds.
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The changes in range margins of birds breeding in Finland was analysed from published atlas data for a 12-year period (1974-1979 to 1986-1989). The change in range margin was statistically corrected for changes in species' distribution using linear regression. For species predominantly occurring in southern Finland (n = 116), the expected range margin shift, if their distribution would not have changed, was 18.8 km northwards. Northerly species (n = 34) showed no such significant range margin shift. A similar result was found earlier for UK birds. Recent range margin shifts in birds therefore seem to be a general phenomenon, which may be related to climate change.
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Changes in geographic distributions of 5 bird species endemic to the Great Plains of North America were examined over the last few decades based on the United States Breeding Bird Survey. Examining the mean latitude of individuals of each species, 3 species showed significant or near-significant northward shifts, and 1 a significant shift southward. Over all 5 species examined, colonization events were concentrated in the northern part of the distributions of the species; in 3 species, extinctions were concentrated in the southern part of the distributions of the species. The conclusion is that significant distributional changes have taken place, but they have been subtle, and might be associated with global climate change.
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While poleward species migration in response to recent climatic warming is widely documented, few studies have examined entire range responses of broadly distributed sessile organisms, including changes on both the trailing (equatorward) and the leading (poleward) range edges. From a detailed population census throughout the entire geographical range of Aloe dichotoma Masson, a long-lived Namib Desert tree, together with data from repeat photographs, we present strong evidence that a developing range shift in this species is a ‘fingerprint’ of anthropogenic climate change. This is explained at a high level of statistical significance by population level impacts of observed regional warming and resulting water balance constraints. Generalized linear models suggest that greater mortalities and population declines in equatorward populations are virtually certainly the result, due to anthropogenic climate change, of the progressive exceedance of critical climate thresholds that are relatively closer to the species’ tolerance limits in equatorward sites. Equatorward population declines are also broadly consistent with bioclimatically modelled projections under anticipated anthropogenic climate change but, as yet, there is no evidence of poleward range expansion into the area predicted to become suitable in future, despite good evidence for positive population growth trends in poleward populations. This study is among the first to show a marked lag between trailing edge population extinction and leading edge range expansion in a species experiencing anthropogenic climate change impacts, a pattern likely to apply to most sessile and poorly dispersed organisms. This provides support for conservative assumptions of species’ migration rates when modelling climate change impacts for such species. Aloe dichotoma's response to climate change suggests that desert ecosystems may be more sensitive to climate change than previously suspected.
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The conservation status of 845 zooxanthellate reef-building coral species was assessed by using International Union for Conservation of Nature Red List Criteria. Of the 704 species that could be assigned conservation status, 32.8% are in categories with elevated risk of extinction. Declines in abundance are associated with bleaching and diseases driven by elevated sea surface temperatures, with extinction risk further exacerbated by local-scale anthropogenic disturbances. The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds that of most terrestrial groups. The Caribbean has the largest proportion of corals in high extinction risk categories, whereas the Coral Triangle (western Pacific) has the highest proportion of species in all categories of elevated extinction risk. Our results emphasize the widespread plight of coral reefs and the urgent need to enact conservation measures.
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It is predicted that climate change will cause species extinctions and distributional shifts in coming decades, but data to validate these predictions are relatively scarce. Here, we compare recent and historical surveys for 48 Mexican lizard species at 200 sites. Since 1975, 12% of local populations have gone extinct. We verified physiological models of extinction risk with observed local extinctions and extended projections worldwide. Since 1975, we estimate that 4% of local populations have gone extinct worldwide, but by 2080 local extinctions are projected to reach 39% worldwide, and species extinctions may reach 20%. Global extinction projections were validated with local extinctions observed from 1975 to 2009 for regional biotas on four other continents, suggesting that lizards have already crossed a threshold for extinctions caused by climate change.
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Significant changes in physical and biological systems are occurring on all continents and in most oceans, with a concentration of available data in Europe and North America. Most of these changes are in the direction expected with warming temperature. Here we show that these changes in natural systems since at least 1970 are occurring in regions of observed temperature increases, and that these temperature increases at continental scales cannot be explained by natural climate variations alone. Given the conclusions from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report that most of the observed increase in global average temperatures since the mid-twentieth century is very likely to be due to the observed increase in anthropogenic greenhouse gas concentrations, and furthermore that it is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent except Antarctica, we conclude that anthropogenic climate change is having a significant impact on physical and biological systems globally and in some continents.
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Mean global temperatures have risen this century, and further warming is predicted to continue for the next 50-100 years. Some migratory species can respond rapidly to yearly climate variation by altering the timing or destination of migration, but most wildlife is sedentary and so is incapable of such a rapid response. For these species, responses to the warming trend should be slower, reflected in poleward shifts of the range. Such changes in distribution would occur at the level of the population, stemming not from changes in the pattern of indivduals' movements, but from changes in the ratios of extinctions to colonizations at the northern and southern boundaries of the range. A northward range shift therefore occurs when there is net extinction at teh southern boundary or net colonization at the northern boundary. However, previous evidence has been limited to a single species or to only a portion of the species' range. Here we provide the first large-scale evidence of poleward shifts in entire species' ranges. In a sample of 35 non-migratory European butterflies, 63% have ranges that have shifted to the north by 35-240 km during this century, and only 3% have shifted to the south.
Aim To estimate whether species have shifted at equal rates at their leading edges (cool boundaries) and trailing edges (warm boundaries) in response to climate change. We provide the first such evidence for tropical insects, here examining elevation shifts for the upper and lower boundaries shifts of montane moths. Threats to species on tropical mountains are considered. Location Mount Kinabalu, Sabah, Malaysia. Methods We surveyed Lepidoptera (Geometridae) on Mount Kinabalu in 2007, 42 years after the previous surveys in 1965. Changes in species upper and lower boundaries, elevational extents and range areas were assessed. We randomly subsampled the data to ensure comparable datasets between years. Estimated shifts were compared for endemic versus more widespread species, and for species that reached their range limits at different elevations. Results Species that reached their upper limits at 2500–2700 m (n= 28 species, 20% of those considered) retreated at both their lower and upper boundaries, and hence showed substantial average range contractions (−300 m in elevational extent and −45 km2 in estimated range area). These declines may be associated with changes in cloud cover and the presence of ecological barriers (geological and vegetation transitions) which impede uphill movement. Other than this group, most species (n= 109, 80% of the species considered) expanded their upper boundaries upwards (by an average of 152 m) more than they retreated at their lower boundaries (77 m). Main conclusions Without constraints, leading margins shifted uphill faster than trailing margins retreated, such that many species increased their elevational extents. However, this did not result in increases in range area because the area of land available declines with increasing elevation. Species close to a major ecological/geological transition zone on the mountain flank declined in their range areas. Extinction risk may increase long before species reach the summit, even when undisturbed habitats are available.
Recent warming has caused changes in species distribution and abundance, but the extent of the effects is unclear. Here we investigate whether such changes in highland forests at Monteverde, Costa Rica, are related to the increase in air temperatures that followed a step-like warming of tropical oceans in 1976 (refs4, 5). Twenty of 50 species of anurans (frogs and toads) in a 30-km2 study area, including the locally endemic golden toad (Bufo periglenes), disappeared following synchronous population crashes in 1987 (refs 6-8). Our results indicate that these crashes probably belong to a constellation of demographic changes that have altered communities of birds, reptiles and amphibians in the area and are linked to recent warming. The changes are all associated with patterns of dry-season mist frequency, which is negatively correlated with sea surface temperatures in the equatorial Pacific and has declined dramatically since the mid-1970s. The biological and climatic patterns suggest that atmospheric warming has raised the average altitude at the base of the orographic cloud bank, as predicted by the lifting-cloud-base hypothesis,.
Aim To investigate altitudinal range shifts of bryophytes in Switzerland by comparing recent altitudinal distributions with historical distributions derived from herbarium specimens. Location Switzerland, covering 41,285 km2 in Central Europe. Methods We used a dataset of 8520 herbarium specimens of 61 bryophyte species and compared altitudinal data between the two periods 1880–1920 and 1980–2005. The records we used were not specifically sampled for climatological analyses, but originate from non-systematic fieldwork by various collectors. Historical and recent records were distributed all over Switzerland with occurrences in all major biogeographical areas. To account for different sampling efforts in the two time periods, different subsampling procedures were applied. Results Overall, we found a significant mean increase in altitude of 89 ± 29 m which was mainly driven by the cryophilous species (+222 ± 50 m). The mean increase in altitude of cryophilous species corresponds to a decadal upward shift of 24 m. The upper range limit of cryophilous species also increased by 189 ± 55 m, but there was no effect on the lower range limit. For intermediate and thermophilous species neither mean, nor upper or lower range limits changed. However, the proportion of records of thermophilous to cryophilous species increased considerably at lower altitudes, but levelled off above approximately 1800 m. Main conclusions We conclude that cryophilous bryophytes are expanding their range to higher elevations in Switzerland and that at lower elevations, a slow extinction process is going on, probably as a result of climate warming trends. The observed decadal upward shifts of cryophilous species closely match those reported from vascular plants in Europe and those expected, given recent estimates of climate warming trends. We emphasize that herbaria provide valuable data that can be used to detect ongoing changes in the distribution of species.