Birds rarely hybridize: A citizen science approach to estimating rates of hybridization in the wild*

The rate of hybridization among taxa is a central consideration in any discussion of speciation, but rates of hybridization are difficult to estimate in most wild populations of animals. We used a successful citizen science dataset, eBird, to estimate the rates of hybridization for wild birds in the United States. We calculated the frequency at which hybrid individuals belonging to different species, families, and orders of birds were observed. Between 1 January 2010 and 31 December 2018, a total of 334,770,194 species records were reported to eBird within the United States. Of this total, 212,875 or 0.064% were reported as hybrids. This estimate is higher than the rate of hybridization (0.00167%) reported by Mayr based on impressions from a career studying museum specimens. However, if the 10 most influential hybrid species are removed from the eBird dataset, the rate of hybridization decreases substantially to about 0.009%. We conclude that the rate of hybridization for individuals in most bird species is extremely low, even though the potential for birds to produce fertile offspring through hybrid crosses is high. These findings indicate that there is strong prezygotic selection working in most avian species.     

THE PLACE OF GOD IN SYNTHETIC BIOLOGY: HOW WILL THE CATHOLIC CHURCH RESPOND?

Some religious believers may see synthetic biology as usurping God's creative role. The Catholic Church has yet to issue a formal teaching on the field (though it has issued some informal statements in response to Craig Venter's development of a 'synthetic' cell). In this paper I examine the likely reaction of the Catholic Magisterium to synthetic biology in its entirety. I begin by examining the Church's teaching role, from its own viewpoint, to set the necessary backround and context for the discussion that follows. I then describe the Church's attitude to science, and particularly to biotechnology. From this I derive a likely Catholic theology of synthetic biology. The Church's teachings on scientific and biotech research show that it is likely to have a generally positive disposition to synbio, if it and its products can be acceptably safe. Proper evaluation of, and protection against, risk will be a significant factor in determining the morality of the research. If the risks can be minimized through regulation or other means, then the Church is likely to be supportive. The Church will also critique the social and legal environment in which the research is done, evaluating issues such as the patenting of scientific discoveries and of life.     

Integrating multiple data sources to assess the distribution and abundance of bottlenose dolphins Tursiops truncatus in Scottish waters

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Teaching Bernoulli's Principle through Demonstrations

ABSTRACT

One proven strategy to help students make sense of abstract concepts is to sequence instruction so students have exploratory opportunities to investigate science before being introduced to new science explanations (Abraham and Renner 1986 Abraham, M. R. and Renner, J. W. 1986. The sequence of learning cycle activities in high school chemistry. Journal of Research in Science Teaching, 23: 121–143. [Crossref], [Web of Science ®] , [Google Scholar]; Renner, Abraham, and Birnie 1988 Renner, J. W., Abraham, M. R. and Birnie, H. H. 1988. The necessity of each phase of the learning cycle in teaching high school physics. Journal of Research in Science Teaching, 25: 39–58. [Crossref], [Web of Science ®] , [Google Scholar]). To help physical science teachers make sense of how to effectively sequence lessons, this article summarizes our experiences using an exploration–explanation sequence of instruction to teach Bernoulli's principle to prospective middle and secondary science teachers in a science methods course. We use demonstrations during our Bernoulli unit to help students go back and forth between their observations of phenomenon and what occurs on the microscopic level with what we have termed molecular talk. Students engage in guiding questions, consider their old and new understandings of science, and use evidence to construct new ideas during all stages of the lesson.     

The Mixed Media Bag

This article provides basic information on how a common species of earthworm, Eisenia fetida, can be used in the biology classroom as well as a discussion of how to establish and care for a vermicompost bin. We discuss ideas for inquiry activities with the organism and provide a sample-guided inquiry that demonstrates how a long-term, theme-based unit involving earthworms can address a wide variety of content from the National Science Education standards.     

Of Cecropias,Snarks and Boojums

We reply to Webber et al. (2011 Webber, BL, Born, C, Conn, BJ, Hadiah, JT and Zalamea, P-C. 2011. What is in a name? That which we call Cecropia peltata by any other name would be as invasive?. Plant Ecology & Diversity, 3: 241–245.  [Google Scholar]). Our study, Sheil and Padmanaba (2011 Sheil, D and Padmanaba, M. 2011. Innocent invaders? A preliminary assessment of Cecropia, an American tree, in Java. Plant Ecology & Diversity, 3: 231–240.  [Google Scholar]), was a preliminary assessment of the alien Neotropical tree Cecropia around Bogor, West Java, Indonesia. We highlighted the need for low-cost assessment approaches for addressing alien species and considered what might be achieved by local actors with limited resources. We successfully characterised the local distribution of Cecropia and identified, addressed and illustrated various concerns. Based on these results we asked how such studies might be useful and how they could be improved. Webber et al. criticise our study but fail to engage with its goals. Certainly, low-input local approaches lack the sophistication and rigour of larger international efforts, but such comparisons are unhelpful. Aside from a number of misunderstandings, we find Webber et al.’s principal arguments overstated, and unsupported by published information. The evidence that Cecropia causes harm is unconvincing; species-level identification is overemphasised; and the insistence on completing detailed research before considering management options is problematic. We offer some positive conclusions and repeat our plea for the development of effective low-input methods for evaluating and addressing naturalised organisms.     

Societal views and animal welfare science: understanding why the modified cage may fail and other stories

The innovations developed by scientists working on animal welfare are often not adopted in practice. In this paper, we argue that one important reason for this failure is that the solutions proposed do not adequately address the societal concerns that motivated the original research. Some solutions also fail because they do not adequately address perceived constraints within the industry. Using examples from our own recent work, we show how research methods from the social sciences can address both of these limitations. For example, those who persist in tail-docking cattle (despite an abundance of evidence showing that the practice has no benefits) often justify their position by citing concern for cow cleanliness. This result informs the nature of new extension efforts directed at farmers that continue to tail dock, suggesting that these efforts will be more effective if they focus on providing producers with methods (of proven efficacy) for keeping cows clean. Work on pain mitigation for dehorning shows that some participants reluctant to provide pain relief believe that the pain from this procedure is short lasting and has little impact on the calf. This result informs the direction of new biological research efforts to understand both the magnitude and duration of any suffering that result from this type of procedure. These, and other examples, illustrate how social science methodologies can document the shared and divergent values of different stakeholders (to ensure that proposed solutions align with mainstream values), beliefs regarding the available evidence (to help target new scientific research that meets the perceived gaps), and barriers in implementing changes (to ease adoption of ideas by addressing these barriers).     

Functional homogenization of flower visitor communities with urbanization

Land‐use intensification and resulting habitat loss are put forward as the main causes of flower visitor decline. However, the impact of urbanization, the prime driver of land‐use intensification in Europe, is poorly studied. In particular, our understanding of whether and how it affects the composition and functioning of flower visitor assemblages is scant, yet required to cope with increasing urbanization worldwide. Here, we use a nation‐wide dataset of plant‐flower visitor (Coleoptera, Diptera, Hymenoptera, Lepidoptera) interactions sampled by citizen scientists following a standardized protocol to assess macroecological changes in richness and composition of flower visitor communities with urbanization. We measured the community composition by quantifying the relative occurrence of generalist and specialist flower visitors based on their specialisation on flowering plant families. We show that urbanization is associated with reduced flower visitor richness and a shift in community composition toward generalist insects, indicating a modification of the functional composition of communities. These results suggest that urbanization affects not only the richness of flower visitor assemblages but may also cause their large‐scale functional homogenization. Future research should focus on designing measures to reconcile urban development with flower visitor conservation.     

The growth characteristics and yield potential of rice (Oryza sativa) under non‐flooded irrigation in arid region

The objectives of this field experiment were to study the growth characteristics and yield potential of rice plants under non‐flooded irrigation in arid area. Non‐flooded treatments included drip irrigation with plastic mulching treatments (DIs), furrow irrigation with plastic mulching treatment (FIM) and furrow irrigation with non‐mulching treatment (FIN). Conventional flooded cultivation (F) was check treatment (CK). The four drip irrigation treatments differed in the amount of water applied before and after panicle initiation. Root length density, leaf dry weight, shoot dry weight and root activity were generally higher in the non‐flood‐irrigated treatments (especially the drip‐irrigated treatments) than in the flood‐irrigated treatment at mid‐tillering. However, the growth and development of rice plants were limited after jointing in the non‐flooded irrigation treatments. Increasing the root/shoot ratio and root length density in the 20–40 cm depth and decreasing specific root length at 0–20 cm soil layer were important mechanisms for helping the rice plants to adapt to the non‐flooded environmental stresses. Finally, the grain yield in the non‐flooded irrigation treatments was lower than that in the F treatment. These low yields were mainly attributed to the low root length density at 0–20 cm depth and root activity. Generally speaking, the restricted degrees in the DIs were smaller than that in the FIM and FIN treatments. Among the DIs, both the highest grain yield (8223–8900 kg ha^?1) and the highest water use efficiency (WUE) (0.63) were observed when the soil water content was kept at ?30 kPa before panicle initiation and at ?15 kPa after panicle initiation (referred to as the DI2 treatment). The yield in the DI2 treatment was not significantly different than that in the flood‐irrigated treatment. However, WUE was 2.5 times higher in the DI2 treatment than in the F treatment. These results suggest that drip irrigation technology can be considered as a better water‐saving cultivation of rice plants in arid region.     

The what,how and why of doing macroecology

Macroecology is a growing and important subdiscipline of ecology, but it is becoming increasingly diffuse, without an organizing principle that is widely agreed upon. I highlight two main current views of macroecology: as the study of large‐scale systems and as the study of emergent systems. I trace the history of both these views through the writings of the founders of macroecology. I also highlight the transmutation principle that identifies serious limitations to the study of large‐scale systems with reductionist approaches. And I suggest that much of the underlying goal of macroecology is the pursuit of general principles and the escape from contingency. I highlight that there are many intertwined aspects of macroecology, with a number of resulting implications. I propose that returning to a focus on studying assemblages of a large number of particles is a helpful view. I propose defining macroecology as “the study at the aggregate level of aggregate ecological entities made up of large numbers of particles for the purposes of pursuing generality”.