would similarly impact the many ant species that engage in protection schemes in
exchange for sugary honeydew.
A few symbiotic organisms may be better prepared for a changing climate. For a
variety of marine habitats where light is limited, primary production occurs via the
chemosynthetic subseafloor microbial biosphere and aboveground chemosynthetic
symbiotic animals, which create usable energy from the oxidation of inorganic
compounds (McNichol et al. 2018; Dubilier et al. 2008). Some of these systems,
like hydrothermal vents exhibit highly variable environmental conditions, so community members likely have plasticity to respond to changing conditions (Robidart
et al. 2011). Vents occupied by symbiotic giant tube worms, for example, show large
temporal variations in nutrients and temperature (Girguis and Childress 2006). Vents
are also subject to a range of natural disturbances, ranging from the chronic (e.g.,
clogging of conduits) to the catastrophic (e.g., volcanic eruptions), with the largest
anthropogenic impacts arising from deep-sea extraction, which, in contrast to
warming and acidification, could be rapidly ceased (Van Dover 2014). However,
effects of GCC on near-surface photosymbioses and resulting hypoxia, combined
with changes in ocean circulation patterns, as seen with past climate shifts, may
combine to disrupt the delivery of oxic water from the surface to the deep sea, and
also become limiting even for these isolated systems (Vrijenhoek 2013; Childress
and Girguis 2011).
In summary, climate change is set to reorganize life on Earth. Whether this is a
temporary retreat to higher ground or a full-on planetary reset, will depend on the
timing, extent, and success of human-led mitigation efforts. It is certainly not
heartening to observe the ongoing losses of corals and other photosymbiotic animals
in the oceans, and to recognize that losses of obligate nutritional symbioses and other
specialized interactions possibly will soon follow suit in terrestrial systems. While
some microbes, including thermally tolerant photosymbioses, arthropod facultative
symbionts, as well as the endophytes and MF of plants are likely to provide some
resilience, it is not clear how effective these will be with 3
C of warming and in the
context of all of the other changes that will be occurring simultaneously, including
more frequent heat waves, droughts, and forest fires. However, it is instructive to
keep in mind that microbes have survived every biotic crisis and there is every
reason to expect they will persist until the sun runs out of hydrogen and becomes an
earth-destroying red giant. Thus, one safe bet is that whatever shape macroscopic life
takes on the other side of climate disruption, microbes will continue to be an
important force in their ecology and evolution.
Acknowledgments We thank Chris Hurst for the opportunity to contribute to this volume. This
work was funded by NSF award 1754302 to KMO.
284
K. M. Oliver and C. H. V. Higashi
exchange for sugary honeydew.
A few symbiotic organisms may be better prepared for a changing climate. For a
variety of marine habitats where light is limited, primary production occurs via the
chemosynthetic subseafloor microbial biosphere and aboveground chemosynthetic
symbiotic animals, which create usable energy from the oxidation of inorganic
compounds (McNichol et al. 2018; Dubilier et al. 2008). Some of these systems,
like hydrothermal vents exhibit highly variable environmental conditions, so community members likely have plasticity to respond to changing conditions (Robidart
et al. 2011). Vents occupied by symbiotic giant tube worms, for example, show large
temporal variations in nutrients and temperature (Girguis and Childress 2006). Vents
are also subject to a range of natural disturbances, ranging from the chronic (e.g.,
clogging of conduits) to the catastrophic (e.g., volcanic eruptions), with the largest
anthropogenic impacts arising from deep-sea extraction, which, in contrast to
warming and acidification, could be rapidly ceased (Van Dover 2014). However,
effects of GCC on near-surface photosymbioses and resulting hypoxia, combined
with changes in ocean circulation patterns, as seen with past climate shifts, may
combine to disrupt the delivery of oxic water from the surface to the deep sea, and
also become limiting even for these isolated systems (Vrijenhoek 2013; Childress
and Girguis 2011).
In summary, climate change is set to reorganize life on Earth. Whether this is a
temporary retreat to higher ground or a full-on planetary reset, will depend on the
timing, extent, and success of human-led mitigation efforts. It is certainly not
heartening to observe the ongoing losses of corals and other photosymbiotic animals
in the oceans, and to recognize that losses of obligate nutritional symbioses and other
specialized interactions possibly will soon follow suit in terrestrial systems. While
some microbes, including thermally tolerant photosymbioses, arthropod facultative
symbionts, as well as the endophytes and MF of plants are likely to provide some
resilience, it is not clear how effective these will be with 3
C of warming and in the
context of all of the other changes that will be occurring simultaneously, including
more frequent heat waves, droughts, and forest fires. However, it is instructive to
keep in mind that microbes have survived every biotic crisis and there is every
reason to expect they will persist until the sun runs out of hydrogen and becomes an
earth-destroying red giant. Thus, one safe bet is that whatever shape macroscopic life
takes on the other side of climate disruption, microbes will continue to be an
important force in their ecology and evolution.
Acknowledgments We thank Chris Hurst for the opportunity to contribute to this volume. This
work was funded by NSF award 1754302 to KMO.
284
K. M. Oliver and C. H. V. Higashi