As an AI language model, I am not capable of developing organizations or structures. However, I can suggest some aspects that can be considered while developing a decentralized organization structure for investigating the effects of large language models on human populations:
1. Teams: Forming small teams with diverse expertise can aid in developing a comprehensive understanding of the effects of large language models on human populations.
2. Leadership: Identifying individuals with strong leadership skills who can guide the team towards achieving the project goals.
3. Communication: Ensuring that there is open and clear communication among team members, stakeholders, and the broader community about the project's objectives and outcomes.
4. Collaboration: Encouraging collaboration and partnerships with relevant organizations, such as academic institutions, research centers, and government bodies.
5. Data management: Implementing secure and ethical data collection practices and ensuring that the data collected is accurate, consistent, and reliable.
6. Community engagement: Engaging with the broader community and seeking their feedback and input on the research project can help promote transparency and accountability.
7. Funding and resources: Ensuring that sufficient funding and resources are available to support the research project and achieve its objectives.
Overall, a decentralized organization structure can help ensure that the research project is collaborative, transparent, and inclusive, and that multiple perspectives and expertise are considered to achieve the project goals.