What makes some creatures more afraid of change than others?

Humans are changing the environment. How wild animals respond to these changes is not clear. Scientists have discovered that the brain works differently in two personality types: those who act fearless and those who are afraid of new things. Being fearless can help wildlife, specifically birds, find new food sources, explore new nesting areas and help them adapt to changes in their environment, but being afraid can also help protect them from dangerous novel things in their environment such as cars.

LSU Department of Biological Sciences Assistant Professor Christine Lattin is the lead author of a paper published in the journal PLOS ONE.

House sparrows can learn from each other, so having a mixture of both personality types in a flock could be part of the reason this species is so successful in human-altered environments. Scientists have found that the genes expressed in the brains of the fearless birds are different from those in the birds that exhibit fear. Three of the four regions of the brain had differences. The hippocampus is associated with learning, memory and spatial navigation.

The hippocampus can play an important role in decision-making. Lattin said that when wildlife are presented with something new in their environment, the genes in their brains respond, helping them process the information, compare it to past experience and decide whether to approach or avoid the novel object.

Three of the six wild female house sparrows acted fearless and three were afraid to approach a new object at their feeding dish, according to the scientists. A red wrist coil, a white plastic cover, a green plastic Easter egg, and a normal silver food dish were novel objects. The fearless birds fed at the food dish regardless of the novel objects while the fearful birds avoided the food dish in the presence of novel objects.

The scientists looked at the genes in four brain regions after behavior testing. The genes in the hippocampus of the fearless birds were different from those in the fearful birds. The fearless birds had many more dopamine receptor 2 transcripts. Dopamine receptor 2 has been associated with exploration. The birds that avoided the new objects had more transcripts for the estrogen receptor alpha gene, which has been associated with anxiety.

Some people struggle with the fear of new things. Lattin said that the genes they have identified could help other scientists develop drugs to target neophobia or anxiety.

The ability to study neurological gene expression in more wild species has been made possible by advances in technology.

Technology has made it cheaper and faster to do these types of analyses. Lattin said that more scientists are doing this type of research now that it is more accessible.

More information: Christine R. Lattin et al, Constitutive gene expression differs in three brain regions important for cognition in neophobic and non-neophobic house sparrows (Passer domesticus), PLOS ONE (2022). DOI: 10.1371/journal.pone.0267180 Journal information: PLoS ONE Citation: What makes some creatures more afraid of change than others? (2022, May 10) retrieved 10 May 2022 from https://phys.org/news/2022-05-creatures.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.