Evolution of Brain Development in Birds

鸟类大脑发育的进化

• 批准号: 0744332
• 负责人: Georg Striedter
• 金额: $ 30万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0744332&HistoricalAwards=false
• 关键词: Evolution; Brain; Development; Birds

The principal aim of the proposed research is to determine what evolutionary changes in developmental mechanisms have caused parrots and songbirds to evolve disproportionately large forebrains. This work is important because disproportionately large forebrains evolved several times independently (e.g., parrots, songbirds, primates, dolphins and whales) and seem to make their bearer's "smart" in a variety of ways. Yet almost nothing is known about how evolution creates enlarged forebrains. Developmental biologists can make genetically modified animals that have unusually large brains because they vary in some aspect of brain development, such as having reduced levels of neuronal cell death. However, these mutant animals tend to die as embryos and never become "smarter". The approach in the proposed work is to inquire of Nature how it manipulated brain development to create "smarter" animals with enlarged forebrains. Specifically, brain development will be compared in a parakeet, a zebra finch and a quail, asking which cellular or molecular mechanisms differ between these species. If Nature used the same mechanism to produce enlarged forebrains in parrots and songbirds, then this suggests the existence of a constraint that must be satisfied in order to obtain well-functioning enlarged forebrains. Knowledge of this constraint would, in turn, inform future attempts to mimic some aspects of brain evolution in laboratory experiments. It would also improve understanding of the mechanisms that underlie the evolution of increased forebrain size and increased intelligence within the human lineage. The proposed work will support the training of two PhD students and at least four undergraduate students who do independent research. The PI is committed to broadening participation of students at all levels and is involved in community outreach programs and monthly series for K-12 students.

这项拟议中的研究的主要目的是确定是什么样的发育机制的进化变化导致鹦鹉和鸣禽进化出不成比例的大前脑。 这项工作很重要，因为不成比例的大前脑独立进化了几次（例如，鹦鹉、鸣禽、灵长类动物、海豚和鲸鱼），而且似乎以各种方式使它们的携带者变得“聪明”。 然而，几乎没有人知道进化是如何创造扩大的前脑的。 发育生物学家可以使转基因动物具有异常大的大脑，因为它们在大脑发育的某些方面有所不同，例如神经元细胞死亡水平降低。 然而，这些突变动物往往在胚胎期就死亡了，永远不会变得“更聪明”。 这项工作的方法是询问自然界如何操纵大脑发育，创造出具有扩大前脑的“更聪明”的动物。 具体来说，我们将比较长尾小鹦鹉、斑胸草雀和鹌鹑的大脑发育，并询问这些物种之间的细胞或分子机制有何不同。 如果大自然使用同样的机制来产生鹦鹉和鸣禽的增大的前脑，那么这表明存在一种限制，必须满足这种限制，才能获得功能良好的增大的前脑。 反过来，对这一限制的了解将为未来在实验室实验中模拟大脑进化的某些方面提供信息。 它还将提高对人类谱系中前脑大小增加和智力增加的进化机制的理解。拟议的工作将支持培训两名博士生和至少四名从事独立研究的本科生。 PI致力于扩大各级学生的参与，并参与K-12学生的社区外展计划和每月系列。