Circling the Drain: The Extinction Crisis and the Future of Humanity

Humanity has triggered the sixth mass extinction episode since the beginning of the Phanerozoic. The complexity of this extinction crisis is centered on the intersection of two complex adaptive systems: human culture and ecosystem functioning, although the significance of this intersection is not properly appreciated. Human beings are part of biodiversity and elements in a global ecosystem. Civilization, and perhaps even the fate of our species, is utterly dependent on that ecosystem’s proper functioning, which society is increasingly degrading. The crisis seems rooted in three factors. First, relatively few people globally are aware of its existence. Second, most people who are, and even many scientists, assume incorrectly that the problem is primarily one of the disappearance of species, when it is the existential threat of myriad population extinctions. Third, while concerned scientists know there are many individual and collective steps that must be taken to slow population extinction rates, some are not willing to advocate the one fundamental, necessary, ‘simple’ cure, that is, reducing the scale of the human enterprise. We argue that compassionate shrinkage of the human population by further encouraging lower birth rates while reducing both inequity and aggregate wasteful consumption—that is, an end to growth mania—will be required. This article is part of the theme issue ‘Ecological complexity and the biosphere: The next 30 years.

És possible evitar un col·lapse de la civilització global?

En el número 48 de la revista L'Espill trobaràs un dossier monogràfic sobre "Cap a un col·lapse de la civilització industrial?", amb contribucions d'Antonio Turiel, Luc Semal, Ernest Garcia, Paul R. Ehrlich, Anne H. Ehrlich i Alain Gras. A més, articles d'Antoni Mora, François Rastier, Simona Škrabec, Joan Ramon Resina, Jacobo Muñoz Veiga, Faust Ripoll Domènech, Tobies Grimaltos Mascarós i Narcís Selles Rigat, així com documents del Manifest «Darrera crida», un full de dietari de Vicent Alonso i una conversa amb Tomàs Llorens

Vertebrates on the Brink as Indicators of Biological Annihilation and the Sixth Mass Extinction

The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7% of the evaluated vertebrates). Around 94% of the populations of 77 mammal and bird species on the brink have been lost in the last century. Assuming all species on the brink have similar trends, more than 237,000 populations of those species have vanished since 1900. We conclude the human-caused sixth mass extinction is likely accelerating for several reasons. First, many of the species that have been driven to the brink will likely become extinct soon. Second, the distribution of those species highly coincides with hundreds of other endangered species, surviving in regions with high human impacts, suggesting ongoing regional biodiversity collapses. Third, close ecological interactions of species on the brink tend to move other species toward annihilation when they disappear—extinction breeds extinctions. Finally, human pressures on the biosphere are growing rapidly, and a recent example is the current coronavirus disease 2019 (Covid-19) pandemic, linked to wildlife trade. Our results reemphasize the extreme urgency of taking much-expanded worldwide actions to save wild species and humanity’s crucial life-support systems from this existential threat

The MAHB, the Culture Gap, and Some Really Inconvenient Truths

Humanity's failure to take adequate actions to stem a likely environmental collapse calls for extraordinary measures to understand and alter human behavior, argues Paul Ehrlich. His Millennium Assessment of Human Behavior (MAHB) aims to chart the path to a sustainable future

Therapies for bleomycin induced lung fibrosis through regulation of TGF-Β1 induced collagen gene expression

This review describes normal and abnormal wound healing, the latter characterized by excessive fibrosis and scarring, which for lung can result in morbidity and sometimes mortality. The cells, the extracellular matrix (ECM) proteins, and the growth factors regulating the synthesis, degradation, and deposition of the ECM proteins will be discussed. Therapeutics with particular emphasis given to gene therapies and their effects on specific signaling pathways are described. Bleomycin (BM), a potent antineoplastic antibiotic increases TGF-Β1 transcription, TGF-Β1 gene expression, and TGF-Β protein. Like TGF-Β1, BM acts through the same distal promoter cis -element of the COL1A1 gene causing increased COL1 synthesis and lung fibrosis. Lung fibroblasts exist as subpopulations with one subset predominately responding to fibrogenic stimuli which could be a specific cell therapeutic target for the onset and development of pulmonary fibrosis. J. Cell. Physiol. 211: 585–589, 2007. © 2007 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55994/1/20972_ftp.pd

The Nuclearization of Biology Is a Threat to Health and Security

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78142/1/bsp.2009.0047.pd

Biodefense Research: A Win-Win Challenge

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63273/1/bsp.2008.1114.pd

Global distribution and conservation of marine mammals

We identified 20 global key conservation sites for all marine (123) and freshwater (6) mammal species based on their geographic ranges. We created geographic range maps for all 129 species and a Geographic Information System database for a 46,184 1°x 1°g rid-cells, ∼10,000-km 2 . Patterns of species richness, endemism, and risk were variable among all species and species groups. Interestingly, marine mammal species richness was correlated strongly with areas of human impact across the oceans. Key conservation sites in the global geographic grid were determined either by their species richness or by their irreplaceability or uniqueness, because of the presence of endemic species. Nine key conservation sites, comprising the 2.5% of the grid cells with the highest species richness, were found, mostly in temperate latitudes, and hold 84% of marine mammal species. In addition, we identified 11 irreplaceable key conservation sites, six of which were found in freshwater bodies and five in marine regions. These key conservation sites represent critical areas of conservation value at a global level and can serve as a first step for adopting global strategies with explicit geographic conservation targets for Marine Protected Areas. biodiversity | conservation priorities | political endemism T he current loss of biological diversity is one of the most severe global environmental problems and probably is the only one that is truly irreversible. Recent studies show that anthropogenic factors are causing increasing rates of extinctions of both populations and species (1-3). Despite their immense value, marine ecosystems are deteriorating rapidly, especially because of habitat degradation, overexploitation, introduction of exotic species, pollution (including noise), acidification, and climate disruption (4, 5), in part because roughly 60% of the world's human population lives within 100 km of a coast, and 20% of ecosystems adjacent to oceans have been highly modified (6, 7). Because of those anthropogenic environmental changes, many species of marine animals have undergone local, regional, or global extinctions (8). Marine mammals provide some of the bestknown cases of population and species extinction through overexploitation. Many species have experienced severe population depletion, and at least three [Caribbean monk seal (Monachus tropicalis), Atlantic gray whale (Eschrichtius robustus), and the Steller's sea cow (Hydrodamalis gigas)] became extinct because of hunting for their fur, blubber, and meat during the 19th and 20th centuries. The most recent extinction, caused by several human activities including illegal hunting for meat and body parts used in traditional medicine, is the baiji (Lipotes vexillifer) from the Yangtze River in China, which was declared extinct in 2008 (9). Understanding geographical variation in species richness and other large-scale patterns can be especially valuable for the establishment of global conservation priorities (10-13). Those patterns, for example, allow assessment of what would be required to preserve all species in a given taxon and to determine critical sites for their conservation Here we present a global analysis of distribution patterns for 129 marine mammals, focusing on the following goals: (i) describing their geographic ranges; (ii) assessing patterns of species richness and composition; and (iii) determining key conservation sites as a basis for understanding global conservation needs. We created a database with the geographic distribution of all 129 species of pinnipeds, cetaceans, sirenians, two species of otters, and the polar bear (24). We followed Reeves et al. (24) and Wilson and Reeder (25) for the basic taxonomic arrangement (SI Appendix). It is important to emphasize, however, that the taxonomy of many marine mammals is still confused. The oceans are the last remaining places where large, charismatic species doubtless remain to be described; new species have been found in the last 20 y. For example, Mesoplodon perrini (a 4-m beaked whale) (26) and Orcaella heinsohni (the 2-m Australian snubfin dolphin) (27) were scientifically described recently. The taxonomic position of many species is controversial and likely to change radically in the future when more data are available. For example, recent studies suggest that there are several species of orcas (28, 29), Bryde's whales (30), and Blue whales (31, 32). The taxonomy of dolphins also is complex. For example, some consider the Amazonian Tucuxi dolphin (Sotalia fluviatilis) to be two species The lack of better distributional data precludes more sophisticated analysis, such as modeling standard habitat suitability, to predict ranges of the majority of marine mammal species on very large scales (36). Any comprehensive consideration of the distribution of cetaceans is hampered by the uneven sighting effort; range maps therefore must be interpreted with caution. To date, descriptive statistical techniques have been used to explore cetacean-habitat relationships for selected species in specific areas. There are fewer studies that examine patterns of species richness and geographic ranges using computationally intensive statistic modeling techniques. The development of models to test specific hypotheses about the ecological processes determining cetacean distributions has just begun (37). Marine spatial planning is clearly a way forward, particularly for the high seas, where nonspatial monitoring is difficult and where data gaps obstruct conventional management approaches (38). Author contributions: S.P. designed research; S.P. performed research; G.C. contributed new reagents/analytic tools; S.P. and G.C. analyzed data; and S.P., P.R.E., and G.C. wrote the paper. The authors declare no conflict of interest. This article is a PNAS Direct Submission. P.K. is a guest editor invited by the Editorial Board. ECOLOGY To make the data from different species as compatible as possible, we used the same source of distribution information for all species. Despite the limitations in present knowledge, it is imperative to evaluate and implement conservation measures in ways that attempt to compensate for the uncertainties. Spatial modeling incorporates data on the environment to generate a spatial prediction of relative density based on the preference for habitats defined by combinations of environmental covariates. The areas identified for the candidate Marine Protected Areas (MPAs) thus provide a good description of distribution available, as informed by features of the habitat that are shown to be important (39). Terrestrial mammal conservation faces similar uncertainties (40, 41), but significant progress has been made in identifying conservation sites critical for species richness, endemism, and endangerment, using data similar to those used in our study. Such knowledge has contributed to the steps that have been taken to protect many species (2, 15-18). Results and Discussion Marine mammals are a polyphyletic group that comprises 129 species grouped in three orders, Cetacea, Sirenia, and Carnivora In terms of richness, the analysis of our 46,184-cell, ∼10,000-km 2 global geographic quadrant grid (Methods) showed that the number of species per cell varied from 1 to 38, with an average of 17 species, across vast regions of the oceans. Interestingly, latitudinal gradients of species richness of marine and land mammals are very different. Marine mammals have undergone considerable anatomical modifications during their evolution. The unique characteristics of the marine ecosystems have resulted in the many different physiological and ecological responses that marine mammals have experienced. These modifications undoubtedly have resulted in energetic constraints. One of several complex structures of the marine environment is a more-or-less unpredictable, patchy distribution of food over large spatial and temporal scales; this patchy distribution almost certainly has contributed to the evolution of marine mammal energetics, especially through its effect upon energy storage and expenditure strategies. Species richness of land mammals increases sharply from temperate latitudes toward the equator. In contrast, species richness in marine mammals has a more northerly temperate component, showing a higher concentration of species (24 species average) between 30°N and 40°S Regions especially rich in marine species ( Political endemic species [i.e., species found in only one country, a restriction that may increase their vulnerability (2)] included seven species; the Baikal seal (Pusa sibirica), the Australian sea lion (Neophoca cinerea), the Galapagos fur seal (Arctocephalus galapagoensis), the Galapagos sea lion (Zalophus wollebaeki), the New Zealand dolphin (Cephalorhynchus hectori), the Hawaiian monk seal (Monachus schauinslandi), and the vaquita (Phocoena sinus) (45). Seven species, among them the New Zealand sea lion (Phocarctos hookeri) and the Australian Snubfin dolphin (Orcaella heinsohni), had restricted ranges. In terms of extinction risk, 10% of all marine mammals are considered vulnerable, 11% endangered, and 3% critically endangered (SI Appendix). Species at risk were found throughout the oceans but were concentrated at higher latitudes, especially near the Aleutian Islands and the Kamchatka Peninsula, where extensive exploitation of whales and seals occurred in the past To assess the conservation challenges to marine mammals, we determined the area (i.e., the number of cells) required to incorporate different percentages (i.e., 10%, 15%, 20%, and 25%) of the geographic ranges of all species, using the Marxan optimization algorithm (Methods). Conserving at least 10% of all of the species' geographic range required ca. 45 million km 2 (5,700 grid cells), roughly equivalent to 12% of the world's ocean area (e.g., two times the extent of the Southern Ocean). This study provides grounds for future assessment of an area-explicit conservation parameter for marine mammals. The "target" of 10% was used so this work would be comparable to our previous papers on terrestrial mammals (15, 46); it also is one of the targets suggested by the Convention on Biological Diversity (47). This Convention has called for networks of protected areas, which, in addition to other conservation measures, are necessary components of sustainable use (39). Targeting 15%, 20%, and 25% of each marine mammal's distribution range considerably increased the area required to meet the targets Our next step was to identify key conservation sites representing all marine mammal species in a geographically explicit way. We selected those sites using the grid cells with the greatest diversity followed by "irreplaceable" cells (i.e., cells with species represented nowhere else), using the Marxan optimization algorithm (Methods). We evaluated the representation of all marine mammal species in 1%, 2.5%, 5%, 7.5%, and 10% of the grid cells PNAS Early Edition | 3 of 6 ECOLOGY servation strategy with MPAs representing all marine mammals, their ecological roles, and some threats (39, 50). The nine key conservation sites selected because of their species richness were along the coasts of Baja California, Northeastern America, Peru, Argentina, Northwestern Africa, South Africa, Japan, Australia, and New Zealand. These sites represent 108 species (84% of all marine mammal species), including five endemic species We analyzed the relationship of three human impacts-climate disruption, ocean-based pollution, and commercial shipping (53)-with grid-cell species richness, using a Spearman rank correlation. As we expected, the three impacts have a significant correlation with species richness (rs = 0.693, n = 46,164, P < 0.01 for climate disruption; rs = 0.666, n = 46,164, P < 0.01 for pollution; and rs =0.678, n = 46,164, P < 0.01 for shipping). Our results indicate the widespread impact of human activities on marine ecosystems and their potential for negatively impacting key marine mammal conservation sites. Around 70% of the highest values for the three impacts were located within or near one of our key conservation sites. Adding other human impacts such as commercial fishing probably will show even stronger impacts of human activities on marine mammal conservation