Extinction rate

The Sixth Mass Extinction: fact, fiction or speculation? (Cowie et al. 2022) Paper addresses false information on the extinction rates. “Denying the crisis, simply accepting it and doing nothing, or even embracing it for the ostensible benefit of humanity, are not appropriate options and pave the way for the Earth to continue on its sad trajectory towards a Sixth Mass Extinction.”

Closing the gap between palaeontological and neontological speciation and extinction rate estimates (Silvestro et al. 2018) “Using simulations and empirical analyses we demonstrate not only that this model explains much of the apparent incongruence between fossils and phylogenies, but that differences in rate estimates are actually informative about the prevalence of different speciation modes.”

Emergence of a sixth mass extinction? (Briggs, 2017) “However, I have found evidence that human-caused extinctions have amounted to only about 1.5 species per year for the last 500 years and that these losses have probably been equalled or surpassed by species born (speciation) during that time.” NOTE! See Cowie et al. (2022) above for criticism of this paper and other works of Briggs.

On the Challenge of Comparing Contemporary and Deep-Time Biological-Extinction Rates (Lamkin & Miller, 2016) “Although anthropogenic activities have reduced the abundance and distribution of countless species and have caused more species extinctions than would be expected in the absence of humans, we conclude that the most appropriate interpretation of the existing data is that the global rate of contemporary extinction is closer to 100 times greater than the (revised) background rate of extinction rather than 1000 times greater.”

Accelerated modern human–induced species losses: Entering the sixth mass extinction (Ceballos et al. 2015) “Even under our assumptions, which would tend to minimize evidence of an incipient mass extinction, the average rate of vertebrate species loss over the last century is up to 100 times higher than the background rate. Under the 2 E/MSY background rate, the number of species that have gone extinct in the last century would have taken, depending on the vertebrate taxon, between 800 and 10,000 years to disappear. These estimates reveal an exceptionally rapid loss of biodiversity over the last few centuries, indicating that a sixth mass extinction is already under way.”

The biodiversity of species and their rates of extinction, distribution, and protection (Pimm et al. 2014) “Current rates of extinction are about 1000 times the background rate of extinction. These are higher than previously estimated and likely still underestimated. Future rates will depend on many factors and are poised to increase.”

Estimating the normal background rate of species extinction (De Vos et al. 2014) “On the basis of these results, we concluded that typical rates of background extinction may be closer to 0.1 E/MSY. Thus, current extinction rates are 1,000 times higher than natural background rates of extinction and future rates are likely to be 10,000 times higher.”

Has the Earth’s sixth mass extinction already arrived? (Barnosky et al. 2011) “Here we review how differences between fossil and modern data and the addition of recently available palaeontological information influence our understanding of the current extinction crisis. Our results confirm that current extinction rates are higher than would be expected from the fossil record, highlighting the need for effective conservation measures.”

Extinction rates should not be estimated from molecular phylogenies (Rabosky, 2010) “I show that when diversification rates vary among lineages, simple estimators based on the birth–death process are unable to recover true extinction rates. This is problematic for phylogenetic trees with complete taxon sampling as well as for the simpler case of clades with known age and species richness. Given the ubiquity of variation in diversification rates among lineages and clades, these results suggest that extinction rates should not be estimated in the absence of fossil data.”

Re-assessing current extinction rates (Stork, 2009) “Here I suggest that climate change, rather than deforestation is likely to bring about such high levels of extinction since the impacts of climate change are local to global and that climate change is acting synergistically with a range of other threats to biodiversity including deforestation.”

Extinction rates can be estimated from molecular phylogenies (Nee et al. 1994) “We illustrate: (i) how molecular phylogenies provide information about the extent to which particular clades are likely to be under threat from extinction; (ii) how cursory analyses of molecular phylogenies can lead to incorrect conclusions about the evolutionary processes that have been at work; and (iii) how different evolutionary processes leave distinctive marks on the structure of reconstructed phylogenies.”

How much do we know about the current extinction rate? (Smith et al. 1993) “These figures are much smaller than those of the Permian/ Triassic and Cretaceous/Tertiary mass extinctions. One might therefore conclude that at present life on earth is at comparatively little risk of extinction. However, there is a growing body of data to show that the converse is true.”

Insect abundance changes over time

30 years brings changes to the arthropod community of Kibale National Park, Uganda (Opito et al. 2023) “Arthropod abundance declined in all areas, but only significantly so in the moderately logged forestry compartment (41%).”

Special Issue: Spotlight on insects: trends, threats and conservation challenges (Insect Conservation and Diversity, march 2020)
“In this special issue of Insect Conservation and Diversity, we present new empirical evidence on insect populations trends, address interacting drivers of change, and identify key challenges for the future.”
Papers:
– Interpreting insect declines: seven challenges and a way forward
– Are insects declining and at what rate? An analysis of standardised, systematic catches of aphid and moth abundances across Great Britain
– Declining abundance of beetles, moths and caddisflies in the Netherlands
– Long‐term monitoring reveals decreasing water beetle diversity, loss of specialists and community shifts over the past 28 years
– Vegetation encroachment drives changes in the composition of butterfly assemblages and species loss in Mediterranean ecosystems
– Glowing, glowing, gone? Monitoring long‐term trends in glow‐worm numbers in south‐east England
– Factors contributing to the decline of an endangered flightless longhorn beetle: A 20‐year study
– Landscape‐level environmental stressors contributing to the decline of Poweshiek skipperling (Oarisma poweshiek)
– Assessing zinc tolerance in two butterfly species: consequences for conservation in polluted environments
– Semantics of the insect decline narrative: recommendations for communicating insect conservation to peer and public audiences
– Marketing insects: can exploiting a commercial framework help promote undervalued insect species?

Complex and nonlinear climate‐driven changes in freshwater insect communities over 42 years (Baranov et al. 2020)
“These changes were accompanied by an 81.6% decline in insect abundance, but an increase in richness (+8.5%), Shannon diversity (+22.7%), evenness (+22.4%) and interannual turnover (+34%).”

Arthropod decline in grasslands and forests is associated with landscape-level drivers (Seibold et al. 2020)
“Overall gamma diversity in grasslands and forests decreased over time, indicating loss of species across sites and regions. In annually sampled grasslands, biomass, abundance and number of species declined by 67%, 78% and 34%, respectively.” … “In 30 forest sites with annual inventories, biomass and species number—but not abundance—decreased by 41% and 36%, respectively.”

Worldwide decline of the entomofauna: A review of its drivers (Sánchez-Bayo & Wyckhuys, 2019)
“Our work reveals dramatic rates of decline that may lead to the extinction of 40% of the world’s insect species over the next few decades.”

Parallel declines in abundance of insects and insectivorous birds in Denmark over 22 years (Møller, 2019)
“The abundance of flying insects was quantified using a windscreen resulting in reductions of 80% and 97% at two transects of 1.2 km and 25 km, respectively, according to general additive mixed model.”

Widespread losses of pollinating insects in Britain (Powney et al. 2019)
“Here we show substantial inter-specific variation in pollinator trends, based on occupancy models for 353 wild bee and hoverfly species in Great Britain between 1980 and 2013. Furthermore, we estimate a net loss of over 2.7 million occupied 1 km2 grid cells across all species. Declines in pollinator evenness suggest that losses were concentrated in rare species. In addition, losses linked to specific habitats were identified, with a 55% decline among species associated with uplands. This contrasts with dominant crop pollinators, which increased by 12%, potentially in response agri-environment measures.”

Climate-driven declines in arthropod abundance restructure a rainforest food web (Lister & Garcia, 2018)
“We compared arthropod biomass in Puerto Rico’s Luquillo rainforest with data taken during the 1970s and found that biomass had fallen 10 to 60 times. Our analyses revealed synchronous declines in the lizards, frogs, and birds that eat arthropods. Over the past 30 years, forest temperatures have risen 2.0 °C, and our study indicates that climate warming is the driving force behind the collapse of the forest’s food web.”

More than 75 percent decline over 27 years in total flying insect biomass in protected areas (Hallmann et al. 2017)
“Our analysis estimates a seasonal decline of 76%, and mid-summer decline of 82% in flying insect biomass over the 27 years of study. We show that this decline is apparent regardless of habitat type, while changes in weather, land use, and habitat characteristics cannot explain this overall decline.”

Influences of extreme weather, climate and pesticide use on invertebrates in cereal fields over 42 years (Ewald et al. 2015)
“Of the 26 invertebrate groups examined, eleven proved sensitive to extreme weather events. Average abundance increased in hot/dry years and decreased in cold/wet years for Araneae, Cicadellidae, adult Heteroptera, Thysanoptera, Braconidae, Enicmus and Lathridiidae.” … “Some long‐term trends in invertebrate abundance correlated with temperature and rainfall, indicating that climate change may affect them. However, pesticide use was more important in explaining the trends, suggesting that reduced pesticide use would mitigate the effects of climate change.”

Ermittlung der Biomassen flugaktiver Insekten im Naturschutzgebiet Orbroicher Bruch mit Malaise Fallen in den Jahren 1989 und 2013 (Sorg et al. 2013)
English version: “Our data confirms, that in the areas studied, less than 25% of the original number of flying insects collected in 1989, were still present in 2013.”

Large carabid beetle declines in a United Kingdom monitoring network increases evidence for a widespread loss in insect biodiversity (Brooks et al. 2012)
“We found substantial overall declines in carabid biodiversity. Three‐quarters of the species studied declined, half of which were estimated to be undergoing population reductions of > 30%, when averaged over 10‐year periods.”

Long‐term changes in the abundance of flying insects (Shortall et al. 2009)
“There was a significant decline in total biomass at Hereford but not at three other sites: Rothamsted, Starcross and Wye.”

Odonata enter the biodiversity crisis debate: The first global assessment of an insect group (Clausnitzer et al. 2009)
“We have found that one in 10 species of dragonflies and damselflies is threatened with extinction. This threat level is among the lowest of groups that have been assessed to date, suggesting that previous estimates of extinction risk for insects might be misleading.”

Long-term population trends in widespread British moths (Conrad et al. 2004)
“The percentage of species displaying significant decreases (54%) was more than double that displaying increases (22%).”

Rapid responses of British butterflies to opposing forces of climate and habitat change (Warren et al. 2001)
“These insects might be expected to have responded positively to climate warming over the past 30 years, yet three-quarters of them declined: negative responses to habitat loss have outweighed positive responses to climate warming.”

Population Trends of Common British Butterflies at Monitored Sites (Pollard et al. 1995)
“Populations of the species which have expanded in range, monitored for varying periods during 1974-92 have, overall, shown significantly more increases than declines in abundance, as have the species with ranges which already occupy most of Britain.”

Reports:

Monitoring of ecosystem function at landscape‐scale demonstrates temporal difference in invertebrate abundance in Kent and South‐East England (Tinsley-Marshall et al. 2020)
” Between 2004 (n=3838) and 2019 (n=667) there was a statistically significant differece in ‘splat density’ of the order of approximately 50%, from an average of 0.2 splats per mile to 0.1 splats per mile.” … ” We found a small but statistically significant positive relationship between vehicle age and splat density, suggesting that modern cars squash more invertebrates that older cars (Figure 3b). This suggests that the signal from the difference in insect abundance is strong enough to be apparent inspite of more efficient sampling by newer vehicles.”

The State of Britain’s Larger Moths 2013 (Fox et al. 2013)
“Across Britain, the total abundance of larger moths declined significantly, by 28%, during the 40-year period from 1968 to 2007.”

Nanoplastics

Micro(nanoplastics) in the marine environment: Current knowledge and gaps (Mendoza et al. 2018)
“The smaller the sizes of plastics are the higher the toxicity and physical damage.”

Fate and occurrence of micro(nano)plastics in soils: Knowledge gaps and possible risks (Hurley & Nizzetto, 2018)
“Regardless, soils in agricultural and urban areas are expected to represent major environmental reservoirs of micro(nano)plastics, possibly comprehensively larger than the marine one. Additionally, soils exhibit several potential exposure pathways for micro(nano)plastics to organism and human health, including contamination of groundwater aquifers.”

An overview of microplastic and nanoplastic pollution in agroecosystems (Ng et al. 2018)
“Based on limited evidence at this point and understanding that the lack of evidence of ecological impact from microplastic and nanoplastic in agroecosystems does not equate to the evidence of absence, we propose considerations for addressing the gaps in knowledge so that we can adequately safeguard world food supply.”

Nanoplastics in the Aquatic Environment (Mattsson et al. 2018)
“This chapter highlights recent findings concerning sources, degradation pathways, and ecotoxicity of the nanoparticles derived from plastic degradation in addition to those intentionally fabricated to their form in aquatic systems.”

Micro(nano)plastics: A threat to human health? (Revel et al. 2018)
“MPs/NPs could potentially induce: physical damages through particles itself, and biological stress through MPs/NPs alone or leaching of additives (inorganic and organic).”

What is a nanoplastic? (Gigault et al. 2018)
“We define nanoplastics as particles unintentionally produced (i.e. from the degradation and the manufacturing of the plastic objects) and presenting a colloidal behavior, within the size range from 1 to 1000 nm.”

Are There Nanoplastics in Your Personal Care Products? (Hernandez et al. 2017)
“This study confirms the (unexpected) presence of nanoplastics in personal care products containing polyethylene microbeads and highlights the need for further studies to characterize the release and distribution of nanoplastic litter in natural aquatic and soil environments.”

Reducing Uncertainty and Confronting Ignorance about the Possible Impacts of Weathering Plastic in the Marine Environment (Jahnke et al. 2017)
“Biofilms that form and grow on plastic affect weathering, vertical transport, toxicity, and uptake of plastic by marine organisms and have been underinvestigated. Laboratory studies, field monitoring, and models of the impact of weathering on plastic debris are needed to reduce uncertainty in hazard and risk assessments for known and suspected adverse effects. However, scientists and decision makers must also recognize that plastic in the oceans may have unanticipated effects about which we are currently ignorant. Possible impacts that are currently unknown can be confronted by vigilant monitoring of plastic in the oceans and discovery-oriented research related to the possible effects of weathering plastic.”

Effects of nanoplastics and microplastics on toxicity, bioaccumulation, and environmental fate of phenanthrene in fresh water (Ma et al. 2016)
“Within the five sizes particles we tested (from 50 nm to 10 μm), 50-nm NPs showed significant toxicity and physical damage to D. magna.”

Polycarbonate and polystyrene nanoplastic particles act as stressors to the innate immune system of fathead minnow (Pimephales promelas) (Greven et al. 2016)
“Exposure of neutrophils to PSNPs or PCNPs caused significant increases in degranulation of primary granules and neutrophil extracellular trap release compared to a nontreated control, whereas oxidative burst was less affected.”

(Nano)plastics in the environment – Sources, fates and effects (da Costa et al. 2016)
“Though their presence has been difficult to adequately ascertain, due to the inherent technical difficulties for isolating and quantifying them, there is an overall consensus that these are not only present in the environment – either directly released or as the result of weathering of larger fragments – but that they also pose a significant threat to the environment and human health, as well.”

Characterisation of nanoplastics during the degradation of polystyrene (Lambert & Wagner, 2016)
“The results clearly show an increase in the formation of nanoplastics over time.”

Nanoplastics in the Aquatic Environment. Critical Review (Koelmans et al. 2015)
“We conclude that hazards of nanoplastics are plausible yet unclear, which calls for a thorough evaluation of nanoplastic sources, fate and effects.”

Micro- and Nano-plastics and Human Health (Galloway, 2015)
“In this article, some of the most widely encountered plastics in everyday use are identified and their potential hazards listed.”

Ingestion of Nanoplastics and Microplastics by Pacific Oyster Larvae (Cole & Galloway, 2015)
“In conclusion, whil micro- and nanoplastics were readily ingested by oyster larvae, exposure to plastic concentrations exceeding those observed in the marine environment resulted in no measurable effects on the development or feeding capacity of the larvae over the duration of the study.”

Nanoplastic Affects Growth of S. obliquus and Reproduction of D. magna (Besseling et al. 2014)
“Nano-PS reduced population growth and reduced chlorophyll concentrations in the algae. Exposed Daphnia showed a reduced body size and severe alterations in reproduction. Numbers and body size of neonates were lower, while the number of neonate malformations among neonates rose to 68% of the individuals.”

Strong Sorption of PCBs to Nanoplastics, Microplastics, Carbon Nanotubes, and Fullerenes (Velzeboer et al. 2014)

Glyphosate effects on earthworms

This is a list of papers on glyphosate effects on earthworms. The list doesn’t contain all papers on the subject and might occasionally be updated.

Harmful effects

Effects of different concentrations of glyphosate (Roundup 360®) on earthworms (Octodrilus complanatus, Lumbricus terrestris and Aporrectodea caliginosa) in vineyards in the North-East of Italy (Stellin et al. 2018)
“Earthworms in untreated terraria were found all alive, while specimens exposed to glyphosate (Roundup 360®) showed a decreasing survival rate and a sharp decline in the number of cocoons.” … “Results indicate the occurrence of some resistance mechanisms on anecic earthworms in vineyards that have been exposed to glyphosate for at least three decades. However in spite of the long period of application of glyphosate the impact of this largely applied herbicide is still serious (up to 26% of mortality) especially on the deep-burrowing earthworms species (Oc. complanatus and L. terrestris).”

Effects of herbicides, glyphosate, on density and casting activity of earthworm, Pheretima (Amynthas) carnosus (Kaneda et al. 2016)
“From these results, the herbicide did not have direct harmful impacts on the earthworm, but would effect on earthworm casting activity through variation of environmental factors, such as litter amount, soil temperature, and soil moisture.”

Toxicity of AMPA to the earthworm Eisenia andrei Bouché, 1972 in tropical artificial soil (Domínguez et al. 2016)
“Our results suggest that earthworms coming from parents grown in contaminated soils may have reduced growth, limiting their beneficial roles in key soil ecosystem functions.” (AMPA = Aminomethylphosphonic acid – one of glyphosate’s main metabolites.)

Survival, Reproduction, Avoidance Behavior and Oxidative Stress Biomarkers in the Earthworm Octolasion cyaneum Exposed to Glyphosate (Salvio et al. 2016)
“These results indicate that environmentally relevant concentrations of GLY (up to 996 µg GLY kg-1 dry soil) did not exert a toxic effect to O. cyaneum.”

Glyphosate-based herbicides reduce the activity and reproduction of earthworms and lead to increased soil nutrient concentrations (Gaupp-Berghausen et al. 2015)
“We demonstrate, that the surface casting activity of vertically burrowing earthworms (Lumbricus terrestris) almost ceased three weeks after herbicide application, while the activity of soil dwelling earthworms (Aporrectodea caliginosa) was not affected. Reproduction of the soil dwellers was reduced by 56% within three months after herbicide application. Herbicide application led to increased soil concentrations of nitrate by 1592% and phosphate by 127%, pointing to potential risks for nutrient leaching into streams, lakes, or groundwater aquifers.”

Glyphosate Sublethal Effects on the Population Dynamics of the Earthworm Eisenia fetida (Savigny, 1826) (Santadino et al. 2014)
“The matrix population model built showed that while the control population had a positive growth rate, both glyphosate treatments showed negative growth rates. The results suggest that under these sublethal effects, non-target populations are at risk of local extinction, underscoring the importance of this type of studies in agrochemical environmental risk assessment.”

Glyphosate herbicide affects belowground interactions between earthworms and symbiotic mycorrhizal fungi in a model ecosystem (Zaller et al. 2014)
“We found that herbicides significantly decreased root mycorrhization, soil AMF spore biomass, vesicles and propagules. Herbicide application and earthworms increased soil hyphal biomass and tended to reduce soil water infiltration after a simulated heavy rainfall. Herbicide application in interaction with AMF led to slightly heavier but less active earthworms. Leaching of glyphosate after a simulated rainfall was substantial and altered by earthworms and AMF.”

Earthworm communities and soil properties in shaded coffee plantations with and without application of glyphosate (García-Pérez et al. 2014)
“Our findings indicated reduced species number, density and biomass of earthworms, and increased net carbon mineralization rate in plots with GBH.”

Exposure Assessment to Glyphosate of Two Species of Annelids (García-Torres et al. 2014)
“O. tyrtaeum was more sensitive to the highest concentration of glyphosate (50,000 mg kg-1), with 100 % mortality by day 7 of exposure, compared with 71 % for E. fetida. Although biomass of O. tyrtaeum was significantly different between the control and 5,000 mg kg-1 dose at day 14, E. fetida was not affected at that concentration, and only showed a significant weight loss after 7 days of exposure to 50,000 mg kg-1. Adverse effects upon adult fecundity and cocoon viability were observed at glyphosate concentrations of 5,000 mg kg-1 and above. Adverse effects were observed at concentrations that greatly exceeded the recommended field application rates of glyphosate.”

Genotoxic effects of glyphosate or paraquat on earthworm coelomocytes (Muangphra et al. 2014)
“This study showed that, at concentrations well below field application rates, paraquat induces both clastogenic and aneugenic effects on earthworm coelomocytes whereas glyphosate causes only aneugenic effects and therefore does not pose a risk of gene mutation in this earthworm.”

Comparative toxicity of two glyphosate-based formulations to Eisenia andrei under laboratory conditions (Piola et al. 2013)
“Median lethal concentration (LC50) showed that glyphosate-A was 4.5-fold more toxic than glyphosate-B. Sublethal concentrations caused a concentration-dependent weight loss, consistent with the reported effect of glyphosate as uncoupler of oxidative phosphorylation. Glyphosate-A showed deleterious effects on DNA and lysosomal damage at concentrations close to the applied environmental concentrations (14.4µg ae cm-2).”

Toxicity of three pesticides commonly used in Brazil to Pontoscolex corethrurus (Müller, 1857) and Eisenia andrei (Bouché, 1972) (Buch et al. 2013)
“Glyphosate showed no toxic effects for either species even at the highest concentration tested (47mga.i.kg-1), although they displayed avoidance behavior at this concentration.”

Toxicity assessment of 45 pesticides to the epigeic earthworm Eisenia fetida (Wang et al. 2012)

Effects of Glyphosate and 2,4-D on Earthworms (Eisenia foetida) in Laboratory Tests (Correia & Moreira, 2010)
“Earthworms kept in glyphosate-treated soil were classified as alive in all evaluations, but showed gradual and significant reduction in mean weight (50%) at all test concentrations. For 2,4-D, 100% mortality was observed in soil treated with 500 and 1,000 mg/kg. At 14 days, 30%–40% mortality levels were observed in all other concentrations. No cocoons or juveniles were found in soil treated with either herbicide. Glyphosate and 2,4-D demonstrated severe effects on the development and reproduction of Eisenia foetida in laboratory tests in the range of test concentrations.”

Effect of Pesticides on the Reproductive Output of Eisenia fetida (Yasmin & D’Souza, 2007)
“The results showed that the pesticide treatment had a marked negative impact on the growth and reproduction of earthworms. Carbendazim and dimethoate were found to cause greater harm to the selected earthworm species than glyphosate.”

Ecotoxicological assessment of the effects of glyphosate and chlorpyrifos in an Argentine soya field (Casabé et al. 2007)
“GLY reduced cocoon viability, decreasing the number of juveniles. Moreover, earthworms avoided soils treated with GLY.” … “Both pesticides caused a reduction in the feeding activity under laboratory and field conditions.”

As the Worm Turns: Eisenia fetida Avoids Soil Contaminated by a Glyphosate-Based Herbicide (Verrell & Van Buskirk, 2004)

Histochemical and histopathological study of the intestine of the earthworm (Pheretima elongata) exposed to a field dose of the herbicide glyphosate (Morowati, 2000)
“These results suggest that glyphosate, even at the recommended field dose, could cause cell death and interfere with non-specific esterases activity of the epithelial lining of the intestine of P. elongata causing at least 50 percent mortality in the population of the worms.”

Glyphosate, 2,4-DB and dimethoate: Effects on earthworm survival and growth (Dalby et al. 1995)

Effect of repeated low doses of biocides on the earthworm Aporrectodea caliginosa in laboratory culture (Springett & Gray, 1992)
“Azinphos-methyl and Glyphosate applied alone, reduced growth the most over the 100 days and at all rates of application.”

Beneficial effects

Inhibition effect of glyphosate on the acute and subacute toxicity of cadmium to earthworm Eisenia fetida (Zhou et al. 2014)
The presence of glyphosate reduced the concentration of Cd in all fractions, especially the intact cells. During a longer period of exposure, the weight loss of earthworm and the total Cd absorption was alleviated by glyphosate.

Subacute toxicity of copper and glyphosate and their interaction to earthworm (Eisenia fetida) (Zhou et al. 2013)
The joint toxicity data showed that the relative weight loss and the uptake of Cu, as well as the superoxide dismutase, catalase and malondialdehyde activities, were significantly alleviated in the present of GPS, which indicated that GPS could reduce the toxicity and bioavailability of Cu in the soil because of its strong chelating effects.

Does glyphosate impact on Cu uptake by, and toxicity to, the earthworm Eisenia fetida? (Zhou et al. 2012)
The mortality rates and whole-worm metal burdens increased significantly with the increasing Cu concentration in solution. However, toxicity of GPS to earthworms was not observed in this study. Furthermore, the presence of GPS could significantly reduce the acute toxicity of Cu to earthworms. The mortality rates decreased sharply and the uptake of Cu was nearly halted in the presence of GPS.

Transgene escape to nature

This is a list of papers relating to transgene escape from genetically modified organisms (mostly crop plants) to the wild populations. The list doesn’t contain all papers on the subject and might occasionally be updated.

“Born to Run”? Not Necessarily: Species and Trait Bias in Persistent Free-Living Transgenic Plants (Ellstrand, 2018)
“Three decades have passed since the first environmental release of transgenic plants, and more than two decades since their first commercialization. Examples of transgenes gone astray are increasingly commonplace. Transgenic individuals have been identified in more than a thousand free-living plant populations.”
“The traits commonly occurring in species with persistent transgenic free-living populations are the following, in descending order of importance: (1) a history of occurring as non-transgenic free-living plants, (2) fruits fully or partially shattering prior to harvest, (3) have small or otherwise easily dispersed seeds, either spontaneously or by seed spillage along the supply chain from harvest to consumer, (4) ability to disperse viable pollen, especially to a kilometer or more, (5) perennial habit, and (6) the transgene’s fitness effects in the recipient environment are beneficial or neutral.”

Transgene escape and persistence in an agroecosystem: the case of glyphosate-resistant Brassica rapa L. in central Argentina (Pandolfo et al. 2018)
“During 2014, wild B. rapa populations that escaped control with glyphosate applications by farmers were found in this area. These plants were characterized by morphology and seed acidic profile, and all the characters agreed with B. rapa description. The dose-response assays showed that the biotypes were highly resistant to glyphosate. It was also shown that they had multiple resistance to AHAS-inhibiting herbicides. The transgenic origin of the glyphosate resistance in B. rapa biotypes was verified by an immunological test which confirmed the presence of the CP4 EPSPS protein and by an event-specific GT73 molecular marker. The persistence of the transgene in nature was confirmed for at least 4 years, in ruderal and agrestal habitats. This finding suggests that glyphosate resistance might come from GM oilseed rape crops illegally cultivated in the country or as a seed contaminant, and it implies gene flow and introgression between feral populations of GM B. napus and wild B. rapa.”

Potential for gene flow from genetically modified Brassica napus on the territory of Russia (Mikhaylova & Kuluev, 2018)
“We observed maximum 4.1% of transgenic seeds in the progeny of Brassica rapa and 0.6% in the progeny of Brassica juncea. The highest intraspecific hybridization rate of 0.67% was observed in separated populations. DNA fragments, typical to both parents, were present in the genome of the hybrids. The risk of gene flow in Russia is relatively low, but it will be problematic to do environmental monitoring on such a big territory.”

An Empirical Assessment of Transgene Flow from a Bt Transgenic Poplar Plantation (Hu et al. 2017)
“The results of this study indicate that gene flow originating from the Bt poplar plantation occurred at an extremely low level through pollen or seeds under natural conditions.”

High-Resolution Gene Flow Model for Assessing Environmental Impacts of Transgene Escape Based on Biological Parameters and Wind Speed (Wang et al. 2016)
“Here, we present a quasi-mechanistic PMGF model that only requires the input of biological and wind speed parameters without actual data from field experiments.”

Experimental assessment of gene flow between transgenic squash and a wild relative in the center of origin of cucurbits (Cruz-Reyes et al. 2015)
“Given that the hybrid and BC progeny were viable and fertile, the escape and persistence of the transgene is possible via wild populations of C. argyrosperma ssp. sororia.”

Quantifying transgene flow rate in transgenic Sclerotinia-resistant peanut lines (Hu et al. 2015)
“The overall transgene flow rate in three cultivars was 0.2094% based on screening over 85,000 seeds. In general, the transgene flow rate greatly declined past 10 m from the transgene source. However, a transgene flow rate of less than 0.05% did occur sporadically at greater distances than 10 m.”

Transgene flow: Facts, speculations and possible countermeasures (Ryffel, 2014)
“Convincing evidence has accumulated that unintended transgene escape occurs in oilseed rape, maize, cotton and creeping bentgrass. The escaped transgenes are found in variant cultivars, in wild type plants as well as in hybrids of sexually compatible species. The fact that in some cases stacked events are present that have not been planted commercially, implies unintended recombination of transgenic traits. As the consequences of this continuous transgene escape for the ecosystem cannot be reliably predicted, I propose to use more sophisticated approaches of gene technology in future.”

Flower‐visiting insects and their potential impact on transgene flow in rice (Pu et al. 2014)
“European honeybees carry viable pollen over long distances, forage on rice flowers regularly and increase the frequency of transgene flow. Insects mediate gene flow in rice more than previously assumed, and this should be taken into consideration during the ecological risk assessment of transgene flow in self‐pollinated and/or anemophilous crops.”

Crossing the divide: gene flow produces intergeneric hybrid in feral transgenic creeping bentgrass population (Zapiola & Mallory-Smith, 2012)
“This first report of a transgenic intergeneric hybrid produced in situ with a regulated transgenic event demonstrates the importance of considering all possible avenues for transgene spread at the landscape level before planting a regulated transgenic crop in the field. Spontaneous hybridization adds a level of complexity to transgene monitoring, containment, mitigation and remediation programmes.”

Performance of hybrids between transgenic oilseed rape (Brassica napus) and wild Brassica juncea: An evaluation of potential for transgene escape (Huangfu et al. 2011)
“The analysis of parental loci transmission revealed a higher transfer ratio of male-specific loci detected in F1 hybrids, suggesting that oilseed rape genetic markers can be transferred at relatively high frequencies to the next generation. Therefore, higher transfer ratio of oilseed rape-specific loci, coupled with variation of populations in fitness-related parameters in F1 hybrids, could complicate environmental risk assessment of transgenic oilseed rape, especially in current agroecosystems with increasing application of glyphosate.”

Glyphosate drift promotes changes in fitness and transgene gene flow in canola (Brassica napus) and hybrids (Londo et al. 2010)
“The results of this study demonstrate the potential for persistence of glyphosate resistance transgenes in weedy plant communities due to the effect of glyphosate spray drift on plant fitness. Additionally, glyphosate drift has the potential to change the gene-flow dynamics between compatible transgenic crops and weeds, simultaneously reducing direct introgression into weedy species while contributing to an increase in the transgenic seed bank.”

Do escaped transgenes persist in nature? The case of an herbicide resistance transgene in a weedy Brassica rapa population (Warwick et al. 2008)
“These observations confirm the persistence of the HR trait over time. Persistence occurred over a 6‐year period, in the absence of herbicide selection pressure (with the exception of possible exposure to glyphosate in 2002), and in spite of the fitness cost associated with hybridization.”

Transgene escape in sugar beet production fields: data from six years farm scale monitoring (Darmency et al. 2007)
“Herbicide-resistant seeds from the progeny of the weed beet were recorded up to 112 m away from the closest transgenic pollen donor.”

A large‐scale field study of transgene flow from cultivated rice (Oryza sativa) to common wild rice (O. rufipogon) and barnyard grass (Echinochloa crusgalli) (Wang et al. 2006)
“There was a high frequency of transgene flow (11%−18%) at 0–1 m, with a steep decline with increasing distance to a detection limit of 0.01% by 250 m. To our knowledge, this is the highest frequency and longest distance of gene flow from transgenic rice to O. rufipogon reported so far.”

Transgene escape: what potential for crop–wild hybridization? (Armstrong et al. 2005)
“We used this approach to assess the potential for transgene escape via hybridization for 123 widely grown temperate crops and their indigenous and naturalized relatives present in the New Zealand flora. We found that 66 crops (54%) are reproductively compatible with at least one other indigenous or naturalized species in the flora. Limited reproductive compatibility with wild relatives was evident for a further 12 crops (10%).”

A Bt Transgene Reduces Herbivory and Enhances Fecundity in Wild Sunflowers (Snow et al., 2003)
“Here, we report the first empirical evidence that wild plants can benefit from a bacterial transgene under uncaged, natural conditions. Cultivated sunflower (Helianthus annuus) is known to hybridize frequently with wild sunflower (H. annuus) in the western and midwestern United States.”
“If Bt sunflowers are released commercially, we expect that Bt genes will spread to wild and weedy populations, limit damage from susceptible herbivores on these plants, and increase seed production when these herbivores are common.”

Potential Persistence of Transgenes: Seed Performance of Transgenic Canola and Wild × Canola Hybrids (Linder, 1998)
“These results suggest that high‐laurate wild–crop hybrids lack germination cuing mechanisms and will germinate primarily at inappropriate times. However, when they do germinate with wild B. rapa, they are likely to compete well with it because the high‐laurate hybrids germinated and grew as fast or faster than their wild parental control. This should provide opportunities for backcrossing to wild B. rapa.”

Increased fitness of transgenic insecticidal rapeseed under insect selection pressure (Stewart et al., 1997)
“Only two plants, both transgenic, survived the winter to reproduce in the natural‐vegetation plots which were dominated by grasses such as crabgrass. However, in plots that were initially cultivated then allowed to naturalize, medium to high levels of defoliation decreased survivorship of nontransgenic plants relative to Bt‐transgenic plants and increased differential reproduction in favour of Bt plants. Thus, where suitable habitat is readily available, there is a likelihood of enhanced ecological risk associated with the release of certain transgene/crop combinations such as insecticidal rapeseed.”

Competitiveness of transgenic sugar beet resistant to beet necrotic yellow vein virus and potential impact on wild beet populations (Bartsch et al., 1996)
“In experimental field releases in 1993 and 1994 in Germany, a small but increasingly clear ‘additive’ ecological advantage of the genetically engineered trait was detected. In both years and all competition treatments, the conventional tolerant variety performed best. An impact of naturalization on natural, non‐agricultural habitats may appear in wild beet populations in Italian seed beet production areas. However, a survey of coastal areas of North‐Eastern Italy found no virus infestation in 1994, suggesting that an increase in wild beet fitness is unlikely to occur.”

Transgenic plants and the environment (Rogers & Parkes, 1995)
“With a continued increase in the range of transgenes, and plant species for which genetic modification is possible, this review attempts to bring together some of the factors that will influence the eventual fate of transgenes in the environment, and the effects that such a dispersal may have.”

Potential Persistence of Escaped Transgenes: Performance of Transgenic, Oil‐Modified Brassica Seeds and Seedlings (Linder & Schmitt, 1995)
“Our results indicate that high‐laurate hybrids, emerged from shallow depths, may experience performance advantages that will allow them to perform as well as their persistent, wild parent.”

Community response to transgenic plant release: predictions from British experience of invasive plants and feral crop plants (Williamson, 1994)
“GMOs, being mainly derived from crop plants, and in some cases with genes that are likely to enhance survival, can be expected to have an appreciable effect on nonagricultural ecosystems, once a range of different constructs have been released. Familiarity is unlikely to be an effective defence against new ecological effects.”

Invaders, weeds and the risk from genetically manipulated organisms (Williamson, 1993)
“Small genetic changes can cause large ecological changes. GMOs will have characters entirely new to that species’ evolutionary history. While most will have little ecological effect, a few may be ecologically and economically damaging.”

Genetically Modified Crops and Hybridization with Wild Relatives: A UK Perspective (Raybould & Gray, 1993)
A review article.

Environmental risks from the release of genetically modified organisms (GMOs)–the need for molecular ecology (Williamson, 1992)
“Applications to release genetically modified organisms (GMOs) into the environment, usually the agricultural environment, are increasing exponentially. Many involve crop plants that are also weeds. Studies of biological invasions and of biological control show that the probability that a genetically new organism establishing itself is small; it is also unpredictable and in some cases could have severe ecological effects. GMOs pose risks both because they will be released in large numbers and because the greater the genetic novelty the greater the possibility of ecological novelty. Molecular ecology is an essential ingredient in ensuring that risks are assessed efficiently.”

Environment Papers

This site will contain lists of research papers on environmental issues.