TY - JOUR
T1 - Hänsel, Gretel and the slime mould - how an external spatial memory AIDS navigation in complex environments
AU - Smith-Ferguson, Jules
AU - Reid, Chris R.
AU - Latty, Tanya
AU - Beekman, Madeleine
PY - 2017/9/21
Y1 - 2017/9/21
N2 - The ability to navigate through an environment is critical to most organisms' ability to survive and reproduce. The presence of a memory system greatly enhances navigational success. Therefore, natural selection is likely to drive the creation of memory systems, even in non-neuronal organisms, if having such a system is adaptive. Here we examine if the external spatial memory system present in the acellular slime mould, Physarum polycephalum, provides an adaptive advantage for resource acquisition. P. polycephalum lays tracks of extracellular slime as it moves through its environment. Previous work has shown that the presence of extracellular slime allows the organism to escape from a trap in laboratory experiments simply by avoiding areas previously explored. Here we further investigate the benefits of using extracellular slime as an external spatial memory by testing the organism's ability to navigate through environments of differing complexity with and without the ability to use its external memory. Our results suggest that the external memory has an adaptive advantage in 'open' and simple bounded environments. However, in a complex bounded environment, the extracellular slime provides no advantage, and may even negatively affect the organism's navigational abilities. Our results indicate that the exact experimental set up matters if one wants to fully understand how the presence of extracellular slime affects the slime mould's search behaviour.
AB - The ability to navigate through an environment is critical to most organisms' ability to survive and reproduce. The presence of a memory system greatly enhances navigational success. Therefore, natural selection is likely to drive the creation of memory systems, even in non-neuronal organisms, if having such a system is adaptive. Here we examine if the external spatial memory system present in the acellular slime mould, Physarum polycephalum, provides an adaptive advantage for resource acquisition. P. polycephalum lays tracks of extracellular slime as it moves through its environment. Previous work has shown that the presence of extracellular slime allows the organism to escape from a trap in laboratory experiments simply by avoiding areas previously explored. Here we further investigate the benefits of using extracellular slime as an external spatial memory by testing the organism's ability to navigate through environments of differing complexity with and without the ability to use its external memory. Our results suggest that the external memory has an adaptive advantage in 'open' and simple bounded environments. However, in a complex bounded environment, the extracellular slime provides no advantage, and may even negatively affect the organism's navigational abilities. Our results indicate that the exact experimental set up matters if one wants to fully understand how the presence of extracellular slime affects the slime mould's search behaviour.
KW - amoeboid organism
KW - extracellular slime
KW - external spatial memory
KW - Physarum polycephalum
KW - protist
KW - navigation
UR - http://www.scopus.com/inward/record.url?scp=85030162419&partnerID=8YFLogxK
U2 - 10.1088/1361-6463/aa87df
DO - 10.1088/1361-6463/aa87df
M3 - Article
AN - SCOPUS:85030162419
SN - 0022-3727
VL - 50
SP - 1
EP - 11
JO - Journal of Physics D: Applied Physics
JF - Journal of Physics D: Applied Physics
IS - 41
M1 - 414003
ER -