Plants produce dangerous chemical and physical defenses that have shaped the physiology and behavior of the herbivorous predators that feed on them. Here we explore the impact that these plant defenses may have had on humans by testing infants' responses to plants with and without sharp-looking thorns. To do this, we presented 8-to 18-month-olds with plants and control stimuli and measured their initial reaching behavior and subsequent object exploration behavior. Half of the stimuli had sharp-looking thorns or pointed parts while the other half did not. We found that infants exhibited both an initial reluctance to touch and minimized subsequent physical contact with plants compared to other object types. Further, infants treated all plants as potentially dangerous, whether or not they possessed sharp-looking thorns. These results reveal novel dimensions of a behavioral avoidance strategy in infancy that would mitigate potential harm from plants.

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Small-group interventions allow for tailored instruction for students with learning difficulties. A crucial first step is the accurate identification of students who need such an intervention. This study investigated how teachers decide whether their students need a remedial reading intervention. To this end, 64 teachers of 697 third-grade students from Germany were asked to rate whether a reading intervention for their students was “not necessary,” “potentially necessary,” or “definitely necessary.” Independent experimenters tested the students’ reading and spelling abilities with standardized tests, and a subsample of 370 children participated in standardized tests of phonological awareness and vocabulary. Findings show that teachers’ decisions with regard to students’ needing a reading intervention overlapped more with results from standardized spelling assessments than from reading assessments. Hierarchical linear models indicated that students’ spelling abilities, along with phonological awareness and vocabulary, explained variance in teachers’ ratings over and above students’ reading skills. Teachers, thus, relied on proximal cues such as spelling skills to reach their decision. These findings are discussed in relation to clinical standards and educational contexts. Findings indicate that the teachers’ assignment of children to interventions might be underspecified, and starting points for specific teacher training programs are outlined.

Background German children do not formally learn letter‐sounds before school entry. In this study, we evaluated kindergarten children's sensitivity to the frequency of letters and visually similar symbols in child‐directed texts, how it develops and whether it predicts early reading abilities. Method In a longitudinal study from kindergarten to primary school, children were asked to judge whether a presented alphabetic (e.g., A) or non‐alphabetic symbol (e.g., #) was a letter. High and low frequency was varied for both types of symbols. Furthermore, we analysed whether later reading abilities were predicted by this letter judgement ability. Results Before school entry, children had difficulties in distinguishing frequent non‐alphabetic symbols from letters. Furthermore, letter judgement in kindergarten predicted reading abilities in first grade. Conclusions Children derive some knowledge about letters from the frequency of co‐occurrence of letters and symbols in texts. The ability to distinguish letters from non‐alphabetic symbols predicts early reading.

Phonological similarity effects are biases to judge words as phonologically similar (i.e., rhyming), even if they are not. First found in rime awareness tasks in preliterates, these biases have recently also been found in proficient adult readers. In this study, we evaluated underlying phonological processing in rime judgment longitudinally, across literacy development. To this end, we created a new rime judgment task (rime; i.e., /t∙aɪ̯∙l/ - /z∙aɪ̯∙l/) with two distractor conditions that varied in size of phonological overlap (body; i.e., /t∙aɪ̯∙l/ - /t∙aɪ̯ ç/; nucleus; i.e., /t∙aɪ̯∙l/ - /r∙aɪ̯∙s/). The task was administered to a group of 61 German-speaking children at four time points across school entry and to 21 adults. Accuracy and latency responses were recorded. Results indicated that children and adults showed phonological similarity effects but the effect decreased gradually over time. However, preliterate children were more sensitive to large compared to small phonological overlap, while the same effect was significantly smaller in literate children and adults. Results suggest that preliterate children are more sensitive to larger grain sizes and become more sensitive to fine-grained units across literacy development. The findings are in line with the assumptions of the psycholinguistic grain size theory.