ReviewAnimal cognition2023
On being a Hydra with, and without, a nervous system: what do neurons add?
Review in Animal cognition, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
5 citing papers in PubMed, 13 citations in OpenAlex.
- Early transitions in the evolution of cognition.History and philosophy of the life sciences · 2025Article
- Piezo proteins, mechano reception and behaviour in Hydra.Scientific reports · 2025Article
- Evolution and Function of the Notch Signaling Pathway: An Invertebrate Perspective.International journal of molecular sciences · 2024Review
- Parallel evolution of gravity sensing.Frontiers in cell and developmental biology · 2024Article
- Chemical cognition: chemoconnectomics and convergent evolution of integrative systems in animals.Animal cognition · 2023Article
Corrections and comments
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Authors and funding
1 author at 1 institution in 1 country.
Funding
Abstract
The small freshwater cnidarian Hydra has been the subject of scientific inquiry for over 300 years due to its remarkable regenerative capacities and apparent immortality. More recently, Hydra has been recognized as an excellent model system within neuroscience because of its small size, transparency, and simple nervous system, which allow high-resolution imaging of its entire nerve net while behaving. In less than a decade, studies of Hydra's nervous system have yielded insights into the activity of neural circuits in vivo unobtainable in most other animals. In addition to these unique attributes, there is yet another lesser-known feature of Hydra that makes it even more intriguing: it does not require its neural hardware to live. The extraordinary ability to survive the removal and replacement of its entire nervous system makes Hydra uniquely suited to address the question of what neurons add to an extant organism. Here, I will review what early work on nerve-free Hydra reveals about the potential role of the nervous system in these animals and point towards future directions for this work.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.