Evolution of specialization in a plant-microbial mutualism is explained by the oscillation theory of speciation.

Specialization in mutualisms is thought to be a major driver of diversification, but few studies have explored how novel specialization evolves, or its relation to the evolution of other niche axes. A fundamental question is whether generalist interactions evolve to become more specialized (i.e., oscillation hypothesis) or if partner switches evolve without any change in niche breadth (i.e., musical chairs hypothesis). We examined alternative models for the evolution of specialization by estimating the mutualistic, climatic, and edaphic niche breadths of sister plant species, combining phylogenetic, environmental, and experimental data on Acmispon strigosus and Acmispon wrangelianus genotypes across their overlapping ranges in California. We found that specialization along all three niche axes was asymmetric across species, such that the species with broader climatic and edaphic niches, Acmispon strigosus, was also able to gain benefit from and invest in associating with a broader set of microbial mutualists. Our data are consistent with the oscillation model of specialization, and a parallel narrowing of the edaphic, climatic, and mutualistic dimensions of the host species niche. Our findings provide novel evidence that the evolution of specialization in mutualism is accompanied by specialization in other niche dimensions.

Good prognosis for hospitalized SLE patients with non-related disease.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by widespread organ involvement. Given the scope of modern treatment, there has been a rise in life expectancy and quality with a mean estimated 5-year survival of 82%-90%. Hence, hospitalizations of SLE patients for non-SLE related causes have not been investigated. Our aim was to characterize the SLE patients admitted to the internal medicine wards, the main diagnosis at admission, and the course of hospitalization and to compare the outcome with the general population. We expected to find a significant difference between the SLE population and the general population regarding hospitalization parameters. However we found a good prognosis for hospitalized SLE patients with non-related disease compared to the non-SLE group. SLE was not a significant prognostic factor for outcome in patients hospitalized in the internal medicine ward for non-related causes. Men with SLE had a worse prognosis during hospitalization when compared to females. The SLEDAI score was not an appropriate prognostic method for the outcome of hospitalization.