Population origin, maternal effects, and hydric conditions during incubation determine embryonic and offspring survival in a desert-dwelling lizard.

While the effects of incubation environment on embryonic development and offspring traits have been extensively studied in oviparous vertebrates, studies into how genetic inheritance (population origin), maternal effects, and incubation environment interact to produce varying phenotypes, are rare. To elucidate the interactive role of those three factors during incubation in shaping offspring phenotypes through hydric conditions, we conducted a fully factorial experiment [arid and semiarid populations × maternal dry and wet treatments (MDT and MWT) × embryonic dry and wet treatments (EDT and EWT)] with a desert-dwelling lacertid lizard (Eremias argus). Female lizards in dry conditions produced larger clutch sizes but smaller eggs. The incubation period and hatching success were significantly affected by embryonic but not by maternal moisture treatments. Eggs in the EDT hatched later than those in the EWT in both arid and semiarid populations. Hatching success was lower in EDT than in EWT in the semiarid population, but not in the arid population. Hatchlings from the EDT had a slower post-hatch increase in body mass than those from the EWT. EDT would decrease the survival rates of hatchlings in the semiarid population only. In addition, structural equation models revealed that population had a stronger effect on embryonic and offspring survival than maternal and embryonic moisture. Our study demonstrates locally adaptive strategies of drought resistance at multiple life-history stages in lizard populations from diverse hydric habitats and highlights the importance of genetic factors in determining embryonic drought resistance in oviparous lizards.

[Effects of Vehicle Emissions on Heavy Metals and Polycyclic Aromatic Hydrocarbons Pollution in Road Dust in Xinxiang].

In this study, samples were taken of the surface dust of main roads in Xinxiang City, and the concentrations of five heavy metals (Cd, Pb, Cr, Cu and Zn) and fifteen polycyclic aromatic hydrocarbons (PAHs) were determined by inductively coupled plasma mass spectrometry (ICP-MS) and gas chromatography-mass spectrometry (GC-MS), respectively. Meanwhile, the effects of vehicle emissions on the pollution characteristics were investigated. The results showed that the concentrations of heavy metals and PAHs ranged from 2.58 to 1560 mg·kg-1 and ND to 1.30 mg·kg-1, respectively. Overall, the concentrations of heavy metals and PAHs increased with a decrease in dust particle size. In terms of composition, the heavy metals were dominated by Zn while the high-molecular-weight PAHs were mainly homologous. In spatial distribution, the concentrations of heavy metals and PAHs were different. The total concentrations of heavy metals in road dust near Renmin Road, Xiaodian Industrial Park, and Cement Plant were the highest, while the high concentrations of PAHs appeared in the dust of Renmin Road, Upper Expressway, and 107 National Highway. Pearson correlation analysis showed that there was no positive correlation between the five heavy metals and fifteen PAHs. Then cluster analysis and factor analysis indicated that the PAHs were greatly affected by vehicle emissions, while the heavy metals were basically unaffected.