Why do some birds carry their chicks?
نویسندگان
چکیده
منابع مشابه
Why do bacterial plasmids carry some genes and not others?
Previous explanations of why bacterial genes for certain "optional" traits tend to occur on plasmids rather than chromosomes are based on an outdated misunderstanding of natural selection. They also fail to explain why certain characters that are ubiquitous in some bacterial species tend to occur on plasmids. This paper shows that all major classes of traits usually associated with plasmids rat...
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Tool use is rare in wild animals, but of widespread interest because of its relationship to animal cognition, social learning and culture. Despite such attention, quantifying the costs and benefits of tool use has been difficult, largely because if tool use occurs, all population members typically exhibit the behavior. In Shark Bay, Australia, only a subset of the bottlenose dolphin population ...
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In the gene-for-gene hypothesis, Flor [19] proposed the existence of avirulence alleles of virulence genes, and that the virulence genes actively conditioned cultivar-specific virulence on hosts. Yet cultivar-specific virulence genes have not been found, and many of the avirulence (ar) genes cloned to date (over 40) do not appear to condition pathogenicity in general, virulence or anything els...
متن کاملWhy do sperm carry RNA? Relatedness, conflict, and control.
Classically, sperm were seen as transcriptionally inactive vehicles for delivering the paternal haplotype to an egg. Yet, it has become apparent that sperm also carry thousands of different RNAs, and the functions of most of these are unknown. Here, we make four novel suggestions for sperm RNA function. First, they could act as relatedness markers facilitating sperm cooperation. Second, they co...
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1. Why are some common and apparently suitable resources avoided by potential users? This interesting ecological and evolutionary conundrum is vividly illustrated by obligate brood parasites. Parasitic birds lay their eggs into nests of a wide range of host species, including many rare ones, but do not parasitize some commonly co-occurring potential hosts. 2. Attempts to explain the absence of ...
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ژورنال
عنوان ژورنال: Ecology
سال: 2017
ISSN: 0012-9658,1939-9170
DOI: 10.1002/ecy.2025