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71.
Roosa AE Laitinen Suvi Broholm Victor A Albert Teemu H Teeri Paula Elomaa 《BMC plant biology》2006,6(1):11-18
Background
The inflorescence of the cut-flower crop Gerbera hybrida (Asteraceae) consists of two principal flower types, ray and disc, which form a tightly packed head, or capitulum. Despite great interest in plant morphological evolution and the tractability of the gerbera system, very little is known regarding genetic mechanisms involved in flower type specification. Here, we provide comparative staging of ray and disc flower development and microarray screening for differentially expressed genes, accomplished via microdissection of hundreds of coordinately developing flower primordia. 相似文献72.
73.
We here present the first behavioral, morphological, and ecological data on a living group of highland pygmy tarsiers, Tarsius pumilus, and compare them with the lowland tarsier species of Sulawesi. Pygmy tarsiers were previously known only from 3 museum specimens
and had not been seen alive since the first specimens were collected in 1917 and 1930. As part of a 2-mo exploratory study,
we recently located a group consisting of ≥4 pygmy tarsiers in the mossy cloud forest of Lore Lindu National Park, Central
Sulawesi, Indonesia. We captured 1 adult female and 2 adult male group members. The tarsiers weighed a mean of 50 g, less
than half the weight of adult lowland tarsiers. Our behavioral observations indicate that these tarsiers live in small groups
that return to the same sleeping tree each morning. Though our data are preliminary, pygmy tarsier body proportions appear
to differ from the lowland Sulawesian tarsier species, with relatively long hind limbs compared to total body length. We also
observed differences in grouping and communication behaviors. Unlike lowland tarsiers, pygmy tarsiers possess multiple adult
males per group and rarely vocalize or scentmark. These differences may correlate with variables unique to their high altitude
habitat, especially a reduction in food and tree resources, given that tree density declined sharply along an altitudinal
gradient. Our preliminary study identifies the importance of altitudinal ecological gradients to tarsier behavioral ecology
in Central Sulawesi, providing questions and predictions for future research directions. 相似文献
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