Adolescent antisocial behaviours:Underlying cognitive and neurobiological processes

Popma, A. [Promotor]Nauta-Jansen, L.M.C. [Copromotor

Possible chemical mimicry of the European lady’s slipper orchid (Cypripedium calceolus)

Pollination based on insect deception has been debated in the scientific community since it was first reported over two hundred years ago. A vast majority of deceptive syndromes occur within the orchid family. While many cheating flowers have been described and are well known, there are still many curious cases that need further investigation. One prime example of such a case is Cypripedium calceolus, known as European lady’s slipper orchid. While the flower has been of interest to many prominent scientists for over a century, its pollination is still not fully understood. Both visual and olfactory cues seem to play an important role in pollinator attraction. In this study we focussed on the olfactory cues in order to explore their relationship (in future experiments) with floral visual cues, including the unique asymmetry of these flowers. Some of the plants’ floral fragrances were used in Electroantennography experiments. Eleven chemical compounds were applied to the antennae of Bombus terrestris and Apis mellifera. Even though these species are not regular visitors of C. calceolus, we were interested to see whether there were common principles in their responses to the flowers’ scent that might justify extrapolating to other pollinator species such as sand bees that get trapped in these orchids and fly out of the flowers afterwards with pollen smeared on their body. The results show that while both species react similarly to most of the odours, some of the tested acetates induced a significantly greater reaction in B. terrestris antennae. These acetates play an important role in bumblebee pheromones, but their relevance for the natural pollinators of C. calceolus remains to be confirmed to see whether chemical mimicry by these flowers is deliberately employed to attract pollinators

Distinción de variantes en color de Serapias perez-chiscanoi (Orchidaceae) en relación con táxones de la Península Ibérica

Serapias perez-chiscanoi has a stable and uniform appearance with green flowers. Throughout its distribution area, however, plants have been found with deviant pink to red flowers that show similarities with other taxa that are occasionally pale flowered. S. perez-chiscanoi is easy to differentiate from S. cordigera subsp. cordigera by the colour of the flowers (S. cordigera subsp. cordigera has red to purple flowers) and the fact that the hypochile dimensions of S. perez-chiscanoi are significantly smaller. It is, however, more difficult to distinguish it from individuals of S. cordigera subsp. gentilii with pale flowers, which occur frequently. The two taxa differ in colour pattern and floral dimensions, especially the hypochile length, which is shorter in S. perez-chiscanoi. Pale-flowered individuals of another species, S. parviflora, are easily distinguished by their significantly smaller flowers. S. perez-chiscanoi occurs in Spain in the autonomous regions of Extremadura and Castilla-La Mancha and in Portugal, S. cordigera subsp. gentilii seems to occur along the coastal regions of SW Portugal, while S. cordigera subsp. cordigera and S. parviflora are distributed throughout the Iberian Peninsula.La Serapias perez-chiscanoi tiene una apariencia estable y uniforme con flores verdes. Sin embargo, a lo largo de su área de distribución, se han encontrado ejemplares de flores con coloraciones desviantes de color rosa hasta rojo que muestran similitudes con otros táxones que presentan ocasionalmente flores pálidas. Serapias perez-chiscanoi es fácil de diferenciar con respecto a S. cordigera subsp. cordigera por el color de las flores (S. cordigera subsp. cordigera tiene flores de rojizas hasta púrpura) y por las dimensiones significativamente más peque - ñas del hipoquilo de S. perez-chiscanoi. Sin embargo es más difícil hacer una distinción con respecto a S. cordigera subsp. gentilii, ya que los individuos de este taxon presentan flores pálidas, lo que ocurre con frecuencia. Estos dos táxones se diferencian por el patrón de colores y por las pequeñas dimensiones de las piezas florales, especialmente el tamaño del hipoquilo más corto en S. perez-chiscanoi. Los individuos de flores pálidas de S. parviflora se pueden distinguir fácilmente gracias a sus flores de pequeño tamaño. Serapias perez-chiscanoi se localiza en España en las comunidades autónomas de Extremadura y Castilla-La Mancha y en Portugal, S. cordigera subsp. gentilii se puede encontrar en las zonas costeras del suroeste de Portugal, mientras que S. cordigera subsp. cordigera y S. parviflora se encuentran en la mayor parte de la Península Ibéric