Conservatism and divergence in communication systems: sound signals of shorebirds and woodpeckers

动物的声音是多种多样的，具有不同的功能和应用。声音被广泛用于保护和管理，以检测或监测不同的物种，包括稀有和濒危物种。例如，啄木鸟用喙击打树木以吸引配偶或宣布领土要求（击鼓）。生物学家可以用这些响亮的鼓声来确定不同啄木鸟物种的存在和丰度。不同物种声音独特的常见原因是（1）有效识别同一物种成员的要求，以及（2）当它们在地理上被一些障碍（如山脉）隔开时，种群之间的快速分化进化。最近的研究令人惊讶地表明，许多动物的声音进化得非常缓慢。一个例子是滨鸟，一个在恐龙时代出现的群体，但即使在远亲物种之间，声音也显示出许多相似之处。拟议的研究计划将调查不同种类的滨鸟和啄木鸟之间的声音显示如何不同，以及这些差异如何适应数百万年来进化保守主义的大局。这些声音进化得很慢，是因为发声器官（“鸣管”）非常简单吗？不同的叫声在表演曲目中一起进化成一个集合，因为所有的叫声都是由一个发声器官产生的吗？如果是这样的话，每一个物种都应该有特定的品质。或者它们可以彼此独立地进化，因为每一种都是以不同的方式产生的？如果一个物种的不同叫声可以或多或少地独立进化，那么一些种类可能进化得很快（例如性叫声），而另一些则进化得很慢（例如通用的警报叫声），这种模式可以通过在该群体的家谱（“家谱”）中检查发声来证明。谜题的最后一部分是发声器官（鸣管），它将从博物馆标本中解剖出来，并与声学展示一起观看，以全面了解鸟类本能的声音和声音产生是如何进化的。

Animal sounds are diverse and have diverse functions and applications. Sounds are widely used in conservation and management to detect or monitor different species, including rare and endangered species. Woodpeckers for example, strike trees with their bills to attract mates or announce territorial claims (drumming"). Biologists can use these loud drumming sounds to determine presence and abundance of different woodpecker species. Common reasons for sounds of different species to be unique are (1) requirements to efficiently identify members of the same species, and (2) rapid divergent evolution between populations when they are separated geographically by some barrier, such as a mountain range. Recent research has surprisingly shown that many animal sounds have evolved extremely slowly. An example is shorebirds, a group that arose in the time of dinosaurs, but that shows many similarities in voice even between distantly related species. The proposed program of research will investigate how sound displays differ among different species of shorebirds and woodpeckers, and how these differences fit into the bigger picture of evolutionary conservatism over millions of years. Do these sounds evolve slowly because the organ of voice ("syrinx") is very simple? Do different calls in the display repertoire evolve together as a set, because all are produced by a single vocal organ? If so, particular qualities should pervade each species' repertoire. Or can they evolve independently of one another, because each is produced in a different way? If different calls of a species can evolve more-or-less independently, then some kinds probably evolve quickly (e.g. sexual calls), and others slowly (e.g. general-purpose alarm calls), a pattern that will be evident by examining vocalizations in the context of the group's phylogeny ("family tree"). The last part of the puzzle is the vocal organ (syrinx), which will be dissected from museum specimens, and viewed alongside acoustic displays, to give a broad picture of how instinctive sounds and sound production evolve in birds.