Collins» team observed that hydras, even with a
relatively simple nervous system, could open their mouths to different degrees — sometimes narrower, sometimes wider.
(1) Gunther S. Stent and David A. Weisblat, «The Development of
a Simple Nervous System» Scientific American 246/1 (1982), 136 - 47.
Using the freshwater polyp Hydra as a model organism, the Kiel - based researchers and their international colleagues investigated how
the simple nervous system of these animals interacts with the microbiome.
There are huge differences between
the simple nervous system of the Caenorhabditis elegans nematode worm — with its 302 neurons and 7000 neural connections — and the network of 85 billion neurons and 100 trillion connections in a human brain.
Because honeybees have less than 1 million neurons, Giurfa says, «you have a combination of extremely rich behavior and
a simple nervous system that you can study.»
That ancestor was probably a flattened, wormlike creature with
a simple nervous system.
A variety of vertebrates and a handful of invertebrates, including octopuses and spiders — even a bacterium — are members of the personality club, but the researchers say sea anemones set a new bar as the animal with
the simplest nervous system.
«It shows that remarkable forms of plasticity can be pervasive anywhere, even in
the simplest nervous systems.»
Hydra has
a simple nervous system, a network of about 600 to 2,000 neurons, depending on the animal's size.
has
a simple nervous system and can be genetically manipulated quickly, the authors were able to screen dozens of genes — many more than were practical in previous studies using mice.
Because C. elegans has
a simple nervous system and can be genetically manipulated quickly, the authors were able to screen dozens of genes — many more than were practical in previous studies using mice.