Capsule: Nest survival of Great Spotted Woodpeckers Dendrocopos major was not related to the abundance or timing of their caterpillar prey, whereas the number of young fledged per nest was higher in ...years with high numbers of defoliating caterpillars and when there was a good temporal match between food demand and the peak caterpillar abundance.
Aims: To test whether the breeding parameters of Great Spotted Woodpeckers were affected by the abundance and timing of their caterpillar prey.
Methods: The breeding parameters of Great Spotted Woodpeckers were monitored in four woods in Hertfordshire, UK, from 2001 to 2016. All nests and their outcomes were followed by regular observations and inspection using nest video cameras; 836 nests were found. The timing and abundance of defoliating caterpillars were monitored using frass trays and damage assessments of oak leaves.
Results: The caterpillar abundance rose to a peak and fell again towards the end of the 16-year study. The date of the maximum frass fall was best predicted by the mean April-May temperature. On average, the date of peak food demand of the young woodpeckers was mismatched with the peak prey by four days. The mean number of young fledged per nest was higher in years with high numbers of defoliating caterpillars and in years when the greatest food demand of the chicks coincided with the peak caterpillar abundance. Nest survival was high and was unrelated to caterpillar abundance or timing.
Conclusion: A high abundance of defoliating caterpillars and good synchronization of timing of breeding with the peak availability of the caterpillars can increase brood productivity of the generalist Great Spotted Woodpecker. A combination of low caterpillar abundance and a warm spring is predicted to reduce productivity considerably.
This paper presents an overview of the current status of the Virtual Atomic and Molecular Data Centre (VAMDC) e-infrastructure, including the current status of the VAMDC-connected (or to be ...connected) databases, updates on the latest technological development within the infrastructure and a presentation of some application tools that make use of the VAMDC e-infrastructure. We analyse the past 10 years of VAMDC development and operation, and assess their impact both on the field of atomic and molecular (A&M) physics itself and on heterogeneous data management in international cooperation. The highly sophisticated VAMDC infrastructure and the related databases developed over this long term make them a perfect resource of sustainable data for future applications in many fields of research. However, we also discuss the current limitations that prevent VAMDC from becoming the main publishing platform and the main source of A&M data for user communities, and present possible solutions under investigation by the consortium. Several user application examples are presented, illustrating the benefits of VAMDC in current research applications, which often need the A&M data from more than one database. Finally, we present our vision for the future of VAMDC.
Abstract
SN 2017dio shows both spectral characteristics of a type-Ic supernova (SN) and signs of a hydrogen-rich circumstellar medium (CSM). Prominent, narrow emission lines of H and He are ...superposed on the continuum. Subsequent evolution revealed that the SN ejecta are interacting with the CSM. The initial SN Ic identification was confirmed by removing the CSM interaction component from the spectrum and comparing with known SNe Ic and, reversely, adding a CSM interaction component to the spectra of known SNe Ic and comparing them to SN 2017dio. Excellent agreement was obtained with both procedures, reinforcing the SN Ic classification. The light curve constrains the pre-interaction SN Ic peak absolute magnitude to be around
M
g
=
−
17.6
mag. No evidence of significant extinction is found, ruling out a brighter luminosity required by an SN Ia classification. These pieces of evidence support the view that SN 2017dio is an SN Ic, and therefore the first firm case of an SN Ic with signatures of hydrogen-rich CSM in the early spectrum. The CSM is unlikely to have been shaped by steady-state stellar winds. The mass loss of the progenitor star must have been intense,
M
˙
∼
0.02
(
ϵ
H
α
/
0.01
)
−
1
(
v
wind
/
500
km s
−1
)
(
v
shock
/
10,000 km s
−1
)
−3
M
⊙
yr
−1
, peaking at a few decades before the SN. Such a high mass-loss rate might have been experienced by the progenitor through eruptions or binary stripping.
FRACTALS: The Secret Code of Creation by Jason Lisle. Green Forest, AR: Master Books, 2021. 224 pages. Paperback; $29.99. ISBN: 9781683442400. *Fractals: The Secret Code of Creation, by Jason Lisle, ...is a beautifully crafted coffee-table book which invites readers not only to the beauty of mathematics, but also to belief in Christianity. The author is affiliated with Answers in Genesis and is a founder of the Bible Science Institute, both of which insist on a young earth interpretation of Genesis 1-3. *The mathematical chapters are well written, but the book is really an apologetic for a narrow Christian worldview. The book claims that mathematics, particularly the Mandelbrot fractal and similar objects, displays God's nature. The first chapter, "The Secret Code," claims that "those who reject God like to explain the complexity of biological life by appealing to Darwinian evolution," but that mathematics is free from this "because numbers do not evolve." The fractals in this book, beginning with the Mandelbrot set, give an "infinitesimal glimpse into the mind of God" (p. 9). This sets the theme: there are only two worldviews, and these are in direct competition. The mathematics of fractals is to lead the reader toward the Christian worldview, indeed to a "secret code." *A computer-generated example of a fractal, introduced by Benoit Mandelbrot,1 is created in the complex plane by iterating the quadratic function f (x) = x2 + c. Pick a complex number c and examine the sequence c, f (c), f (f (c)), and so on. Ask the question, "Do these iterates of the function form a bounded sequence?" If the sequence is bounded, then the complex number c is in the Mandelbrot set. In the complex plane, color that point, c, black. If the sequence c, f (c), f (f (c)), … is not bounded, give c a color based on the speed of growth of the sequence. Use a modern computer to color the points in the complex plane. With this coloring, the mathematical analysis of the Mandelbrot set gives rise to intricate paintings of the complex plane. *After this introduction, the book describes the required mathematical material: sets, complex numbers, function iteration. The mathematical descriptions are well done and intended for a popular audience. There are no frightening equations to drive away the reader. The prose, along with the accompanying artwork, is inviting. One might use much of this book as an invitation into the study of mathematics. Indeed, many mathematicians have used the study of fractals to do just that. *Chapters two through seven explore the mathematics of the Mandelbrot set with text-printed elegant pictures of various regions of the fractals. Chapters two through five, with picturesque titles--"Valley of the Seahorses," "Valley of the Double Spirals," "Infinite Elephants, Scepters on Seahorses"--focus on a particular region of the Mandelbrot set, zooming in to display intricate spirals, bays, peninsulas. The infinite complexity of these drawings is beautiful and agrees with my belief that mathematics is the language of the great artist. *The sixth chapter, "Changing the Formula," asks what happens if the simple quadratic f (x) = x2 + c is replaced by other quadratics. It is shown, by examples, that other quadratics merely transform the Mandelbrot set, shifting it in some obvious manner. A mathematics student comfortable with function transformations will recognize that any quadratic function can be transformed into any other quadratic--this is the essence of the quadratic formula--and so it should not be surprising that nothing new is achieved by replacing one quadratic by another. *Later chapters replace a quadratic function by other polynomials, then by functions involving fractional exponents, then by a conjugate function and finally by trigonometric and exponential functions. Euler's marvelous identity eiθ = cosθ + i sinθ briefly comes into play, linking trigonometric and exponential functions in the complex plane. In all these chapters, the mathematical explanations are kept simple, and the beautiful artwork continues. The chapter, "Geometric and 3D Fractals," asks about higher dimensional figures and introduces the quaternions. The chapter does not go deeply into the material but intends to leave the reader curious and intrigued. The concluding chapter describes occurrences of fractals as physical objects in nature (shorelines, clouds, trees, etc.), returning to the topic found in Mandelbrot's introductory book. *Chapter 8, "Fractals and the Christian Worldview," is an interlude to the mathematics, returning to the claim that of the two suppositions, a Christian or a non-Christian worldview, only the Christian worldview truly explains fractals. Yes, the infinite complexity of the Mandelbrot set is beautiful. Many mathematicians agree that beautiful objects like this are independent of human thought, a form of mathematical platonism. But the leap from mathematical platonism to belief in a creator and then to belief in the biblical God is not well supported by Lisle. He ignores the difficulties involved in these steps: first from mathematical platonism to deism, and then from deism to belief in the God that Christians worship. *In the final (twelfth) chapter, Lisle returns to his argument that mathematics points to the God of the Bible. He quotes physicist Eugene Wigner's article, "The Unreasonable Effectiveness of Mathematics in the Natural Sciences," which discusses the "miracle" of mathematics in explaining the modern world.2 Lisle then quickly dismisses other religious views and claims that only the Bible makes sense of our universe. The book ends with a gospel presentation. *One can argue (Rom. 1:20) that God's divine nature is visible in the beauty of mathematics, but Lisle quickly dismisses the beliefs of atheists and non-Christian religions and leaps to claiming (as implied by the book's subtitle) that the only legitimate reaction to fractals is to believe in the Christian God. While most of my mathematical colleagues identify with mathematical platonism, their beliefs vary across a spectrum from atheism/agnosticism through Judaism, Islam, and Christianity. The jarring leap from "the beauty of fractals comes not from people" (p. 125) to the Christian worldview, will leave a thoughtful skeptic with whiplash. At no place is the "secret code" to creation explained explicitly. *Lisle's approach to apologetics is that of presuppositionalism. He assumes that only a Christian worldview is reasonable. However, presuppositional apologetics has several significant flaws. It can quickly become a circular argument: if one assumes the truth and accuracy of the Bible as an axiom then the Christian worldview is a foregone conclusion. This approach receives quick approval from people who already believe the scriptures but is readily dismissed by the sceptic. Even when the circular argument is avoided, the best one can argue is that the universe--and mathematics--appears to be beautiful, appears to have design. The appearance of design is roughly equivalent to mathematical platonism and parallels the argument of Romans 1. But the sceptic who accepts this argument will immediately point out that there are many worldviews that begin with this assumption. The leap to the Christian worldview is not proven by this approach; it requires the additional confirmation of special revelation. *In other publications, Lisle rejects both the big bang theory and evolution. Ironically, this beautiful book on fractals makes it clear that elegant and complex structures do indeed arise from quite simple processes. This is a concept that underlies the theory of evolution, which Lisle opposes. *Would I put this book on my coffee table? No, because ultimately this book is an attempt at apologetics. The flaw in the apologetics will be apparent to the thoughtful sceptic. And the author's attempt to establish the Christian worldview includes simplistic claims that are dismissive of people with other beliefs. *Notes *1Benoit B. Mandelbrot, The Fractal Geometry of Nature (New York: W. H. Freeman, 1982). *2E. P. Wigner, "The Unreasonable Effectiveness of Mathematics in the Natural Sciences," Communications on Pure and Applied Mathematics 13 (1960): 1-14. *Reviewed by Ken W. Smith, Professor of Mathematics, retired, Manton, MI 49663.
Capsule: There has been no trend in nest survival of Lesser Spotted Woodpecker Dryobates minor in the 70 years since the 1940s whereas the numbers of young per nesting attempt has declined. Late ...nests in any year are now significantly less productive than early ones.
Aims: To test whether there has been a long-term decline in the nest survival and productivity of the Lesser Spotted Woodpecker in Britain.
Methods: Breeding data from 331 nests over the period 1949-2019 have been analysed. There were three sources - nest records submitted to the British Trust for Ornithology, a study by the Royal Society for the Protection of Birds from 2006 to 2009 and records submitted to the Woodpecker Network from 2015 to 2019. Generalized linear models were used to analyse the records for first egg date, clutch size, numbers of young fledged, and numbers of nest days for which the nest was under observation. Data were grouped into three periods reflecting population trends of the bird (pre-1980, 1980-1999, 2000-2019) and we also analysed trends with year and spring temperature.
Results: There was no trend in first egg date up to 1980 but subsequently it has advanced by 13 days. The mean clutch was 5.3 with no trend with period or year. There were no trends in nest survival during the egg stage or chick rearing. The mean number of young fledged was 2.6, with nests since 1980 fledging lower numbers of young than those pre-1980 and a decline with year. Loss of chicks, probably to starvation, was the main cause of low productivity. In the last period (2000-2019) nests started early in the season fledged more young than those started later, a trend not apparent in the earlier periods.
Conclusions: Low productivity is a widespread problem for the Lesser Spotted Woodpecker which has probably been exacerbated by the trend towards warm springs.
On 2019 January 5 a streamer associated with the 4-10 km main belt asteroid (6478) Gault was detected by the ATLAS sky survey, a rare discovery of activity around a main belt asteroid. Archival data ...from ATLAS and Pan-STARRS1 show the trail in early 2018 December, but not between 2010 and 2018 January. The feature has significantly changed over one month, perfectly matching predictions of pure dust dynamical evolution and changes in the observing geometry for a short release of dust around 2018 October 28. Follow-up observations with the Hubble Space Telescope (HST) show a second narrow trail corresponding to a brief release of dust on 2018 December 30. Both releases occurred with negligible velocity. We find the dust grains to be fairly large, with power-law size distributions in the 10−5−10−3 m range and power-law indices of ∼−1.5. Three runs of ground-based data find a signature of ∼2 hr rotation, close to the rotational limit, suggesting that the activity is the result of landslides or reconfigurations after Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) spin-up.
•Halophytic plant species are migrating into glycophytic dominated habitats.•Drivers and mechanisms of the ecotone migration are reviewed.•Internal positive feedback is a double-edged sword.•Next ...generation coastal ecotone model should include internal feedbacks.
Coastal ecosystems are especially vulnerable to global change; e.g., sea level rise (SLR) and extreme events. Over the past century, global change has resulted in salt-tolerant (halophytic) plant species migrating into upland salt-intolerant (glycophytic) dominated habitats along major rivers and large wetland expanses along the coast. While habitat transitions can be abrupt, modeling the specific drivers of abrupt change between halophytic and glycophytic vegetation is not a simple task. Correlative studies, which dominate the literature, are unlikely to establish ultimate causation for habitat shifts, and do not generate strong predictive capacity for coastal land managers and climate change adaptation exercises. In this paper, we first review possible drivers of ecotone shifts for coastal wetlands, our understanding of which has expanded rapidly in recent years. Any exogenous factor that increases growth or establishment of halophytic species will favor the ecotone boundary moving upslope. However, internal feedbacks between vegetation and the environment, through which vegetation modifies the local microhabitat (e.g., by changing salinity or surface elevation), can either help the system become resilient to future changes or strengthen ecotone migration. Following this idea, we review a succession of models that have provided progressively better insight into the relative importance of internal positive feedbacks versus external environmental factors. We end with developing a theoretical model to show that both abrupt environmental gradients and internal positive feedbacks can generate the sharp ecotonal boundaries that we commonly see, and we demonstrate that the responses to gradual global change (e.g., SLR) can be quite diverse.
The ecological effects of tropical cyclones on mangrove forests are diverse and highly location- and cyclone-dependent. Ecological resistance, resilience, and enhancement are terms that describe most ...mangrove forest responses to tropical cyclones. However, in the most extreme cases, tropical cyclones can trigger abrupt and irreversible ecological transformations (i.e., ecological regime shifts). Here, we examine a cyclone-induced ecological regime shift that occurred in Everglades National Park (USA), where forest mortality and peat collapse due to a powerful tropical cyclone (the 1935 Labor Day Hurricane) led to the conversion of mangrove forests to mudflats and an estimated elevation loss of approximately 75 cm. We investigated soil elevation change measured in these mangrove forests and adjacent mudflats during a twenty-year period 1998–2018 using Surface Elevation Table-Marker Horizon (SET-MH) methods. This period encompasses the effects of Hurricanes Wilma (2005) and Irma (2017). We also used historical sea-level rise rates and future sea-level rise scenarios to estimate surface elevation changes in the past (1930–1998) and to illustrate elevation gains needed for these ecosystems to adapt to future change. Collectively, our findings advance understanding of the long-term effects of cyclone-induced ecological regime shifts due to forest mortality, peat collapse, and conversion of mangrove forests to mudflats.
Rheumatic heart disease (RHD) is almost entirely preventable, but its incidence in indigenous Australians remains one of the highest in the world. A community-based echocardiogram screening program ...of 862 Torres Strait Islander children identified 25 (2.9%) new cases of RHD. Among these 25 children, 5/7 (71%) prior acute rheumatic fever presentations had not been recognized. There was a history of microbiologically confirmed group A Streptococcus infection in 17/25 (68%) children with RHD compared with 9/25 (36%) controls (odds ratio OR 95% CI: 3.78 1.17-12.19, P = 0.03). This was more likely to be a skin swab (16/25 64% cases versus 6/25 24% controls) than a throat swab (1/25 4% cases versus 3/25 12% controls) (OR 95% CI: 5.33 1.51-18.90 P = 0.01), supporting a role for skin infection in RHD pathogenesis. Household crowding and unemployment were common in the cohort, emphasizing the need for prioritizing strategies that address the social determinants of health.
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