TY - JOUR
T1 - Environmental DNA metabarcoding reveals temporal dynamics but functional stability of arthropod communities in cattle dung
AU - Thomassen, Emil Ellegaard
AU - Sigsgaard, Eva Egelyng
AU - Jensen, Mads Reinholdt
AU - Olsen, Kent
AU - Hansen, Morten D.D.
AU - Thomsen, Philip Francis
N1 - Publisher Copyright:
© 2024 The Author(s). Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.
PY - 2024/8
Y1 - 2024/8
N2 - Terrestrial invertebrates are highly important for the decomposition of dung from large mammals. Mammal dung has been present in many of Earth's ecosystems for millions of years, enabling the evolution of a broad diversity of dung-associated invertebrates that process various components of the dung. Today, large herbivorous mammals are increasingly introduced to ecosystems with the aim of restoring the ecological functions formerly provided by their extinct counterparts. However, we still know little about the ecosystem functions and nutrient flows in these rewilded ecosystems, including the dynamics of dung decomposition. In fact, the succession of insect communities in dung is an area of limited research attention also outside a rewilding context. In this study, we use environmental DNA metabarcoding of dung from rewilded Galloway cattle in an experimental set-up to investigate invertebrate communities and functional dynamics over a time span of 53 days, starting from the time of deposition. We find a strong signal of successional change in community composition, including for the species that are directly dependent on dung as a resource. While several of these species were detected consistently across the sampling period, others appeared confined to either early or late successional stages. We believe that this is indicative of evolutionary adaptation to a highly dynamic resource, with species showing niche partitioning on a temporal scale. However, our results show consistently high species diversity within the functional groups that are directly dependent on dung. Our findings of such redundancy suggest functional stability of the dung-associated invertebrate community, with several species ready to fill vacant niches if other species disappear. Importantly, this might also buffer the ecosystem functions related to dung decomposition against environmental change. Interestingly, alpha diversity peaked after approximately 20–25 days in both meadow and pasture habitats, and did not decrease substantially during the experimental period, probably due to preservation of eDNA in the dung after the disappearance of visiting invertebrates, and from detection of tissue remains and cryptic life stages.
AB - Terrestrial invertebrates are highly important for the decomposition of dung from large mammals. Mammal dung has been present in many of Earth's ecosystems for millions of years, enabling the evolution of a broad diversity of dung-associated invertebrates that process various components of the dung. Today, large herbivorous mammals are increasingly introduced to ecosystems with the aim of restoring the ecological functions formerly provided by their extinct counterparts. However, we still know little about the ecosystem functions and nutrient flows in these rewilded ecosystems, including the dynamics of dung decomposition. In fact, the succession of insect communities in dung is an area of limited research attention also outside a rewilding context. In this study, we use environmental DNA metabarcoding of dung from rewilded Galloway cattle in an experimental set-up to investigate invertebrate communities and functional dynamics over a time span of 53 days, starting from the time of deposition. We find a strong signal of successional change in community composition, including for the species that are directly dependent on dung as a resource. While several of these species were detected consistently across the sampling period, others appeared confined to either early or late successional stages. We believe that this is indicative of evolutionary adaptation to a highly dynamic resource, with species showing niche partitioning on a temporal scale. However, our results show consistently high species diversity within the functional groups that are directly dependent on dung. Our findings of such redundancy suggest functional stability of the dung-associated invertebrate community, with several species ready to fill vacant niches if other species disappear. Importantly, this might also buffer the ecosystem functions related to dung decomposition against environmental change. Interestingly, alpha diversity peaked after approximately 20–25 days in both meadow and pasture habitats, and did not decrease substantially during the experimental period, probably due to preservation of eDNA in the dung after the disappearance of visiting invertebrates, and from detection of tissue remains and cryptic life stages.
KW - arthropods
KW - cattle dung
KW - colonization
KW - dung beetles
KW - dung degradation
KW - ecosystem functions
KW - eDNA metabarcoding
KW - succession
UR - http://www.scopus.com/inward/record.url?scp=85195883739&partnerID=8YFLogxK
U2 - 10.1111/1365-2656.14119
DO - 10.1111/1365-2656.14119
M3 - Journal article
C2 - 38864368
AN - SCOPUS:85195883739
SN - 0021-8790
VL - 93
SP - 1003
EP - 1021
JO - Journal of Animal Ecology
JF - Journal of Animal Ecology
IS - 8
ER -