Development of behaviour Flashcards
Name types of controls of behaviours
Innate behaviours- Not flexible, they don’t change over the lifestyle of an organism so there must be an underlying genetic control for this behaviour.
Single gene control of behaviour.
Interaction between genes and the environment.
Nature and nurture.
Complex behaviours often involve age-related changes and learning.
Hormones and development.
What are Instinct and innate behaviours and give an example
Many animals show complex behaviour patterns from birth.
Instinctive behaviours are genetically inherited, do not require learning and have little or no developmental plasticity.
There is a genetic component to most behaviours.
For example eel Anguilla anguilla= Eels only reproduce once during there lifetime and then they die. Adult eels migrate down rivers and shallow coastal seas to the edge of the continental separation, then they travel over to the Sargasso sea. It takes 1-2 years. Adults don’t eat so they use everything to keep them swimming probably at great depth. They are starving and have just preserved the testis and ovaries. Eggs are buoyant and float up to the surface. The juvenile eels undergo stages of development in sargasso sea then they migrate back home e.g european eels to european waters. How do they know where to go? The information couldn’t have been passed except genetically
Human babies
Human babies respond strongly to human Faces
Using good quality images of human faces and eye tracking, we can see that the baby will look at that for a long time but if you give them the face of a monkey they don’t spend as much time looking at it therefore somewhere encoded in our genes makes us more likely to look at human faces for longer.
Genes and behaviour .
Name a specific genes that effects learning in mice.
Give two other example f genes effecting behaviour
There are a few known examples where a single gene affects behaviour.
Calcium-calmodulin kinase.
When wild mice are exposed to a trial of this kinase they improve their learning a lot by the second day.
In mice where the gene is not there the Calcium-calmodulin kinase won’t really increase the rate of learning.
wild mice learn to avoid predators and pick things up quicker
The per gene in Drosophila controls circadian rhythms.
The fosB gene affects maternal behaviour in mice.
Mutant females retrieve fewer displaced pups than wild-type females
Taste-receptor gene determines whether we taste toxins
The hTAS2R38 gene determines humans’ bitterness perception of glucosinolates.
Sensitive (PAV/PAV) subjects rated glucosinolate–generating vegetables (e.g. broccoli & sprouts) as 60% more bitter than did the insensitive (AVI/AVI) subjects.
Heterozygotic subjects (PAV/AVI) gave intermediate results.
Population genetic differences in behaviour
Coastal Garter snakes feed on slugs, inland they eat frogs.
Young, naive snakes were offered slugs in experiments:
Snakes from coastal populations ate the slugs.
Snakes from inland populations rejected them.
Age-related development of behaviour in honeybees.
Differential expression of genes, e.g. Amfor.
In honey bees
bees have changes in regulation of genes hence different behaviours are shown by honey bees, and at certain ages the gene AM4 under strong genetic control controls amount of foraging. By changing regulation we can create complex patterns
At the start of a bees life, 5 days in they focus on hygiene bahaviours.
5-15 days most worker bees are in the hive and are feeding and feed larvae in honeycomb.
10-15 days bees leave the hives
12-20 they leave and start packing pollen
15-28 they start foraging where behaviour just increases until they die
Give an example of the role of both genes and the environment on the development of behaviour.
Song learning in birds
Experiments rearing young birds in acoustic isolation demonstrates that they have an innate template for their song.
using sonograms from two species and simple time frequency graphs we can see swamp sparrow and song sparrows songs
Now sparrows are either deafened or reared in a sound proof box without ever hearing adult song. We can see that there is still some similarities in the songs roughly same band of frequencies therefore, it is a species dependent element and these seem to be encoded for genetically but in both cases the innate song is quite crude missing lots of the refined notes.
crucial period of song learning is in the first months of their life and they don’t start singing until sexual maturity. They adapt this species specific template of the song and then listen to the species around. In different locations birds have different accents.
The fine tuning of the template involves learning and input of environment as well as genes.
Black cap as an example of Orientation and navigation
Blackcaps from northern populations migrate west; those from southern populations head south west.
Birds reared in the lab from eggs show the same behaviour as their parent populations.
Population genetic differences.
underlying genes allow for certain populations to migrate in certain directions.
If these two types of birds hybridize we get an intermediate migration direction
Give another example of orientation and navigation using black and common redstart birds
Further migration distance means birds need to migrate earlier such as common redstart.
black redstart can fatten up and stay in same place of hatching longer as they only have a short distance to travel
hybrids have intermediate time between hatching and migrating due to the certain alleles in the genes.
Orientation and navigation with factors or the environment affecting this in starlings
Hybrid behaviour demonstrates that there is a substantial genetic component to migratory behaviour in birds.
But, migratory behaviour is modified by experience.
Starlings travel a southern western direction from Netherlands to the UK normally but instead they took the juveniles and some mature starlings to Switzerland.
The mature experienced birds that had already migrated went to the UK even if that’s a northern western whereas the juveniles went to spain in a southern western direction
There is clear evidence that direction of migration has a gene underlying to go southwest but through experience and the environment that can change orientation to travel to the same place.
Hormones and development
Gene–environment interactions are evident in the development of sexual behaviour.
When considering gene expression, the environment encompasses everything which may affect that gene:
hormones can have imeridate and long term effect of genes as they control the enviromet of the genes.
Other genes in genome.
Cellular environment.
Physiology of the individual.
Environment of the individual.
Zebra finches and hormones
HVC is the song system of males, it is an area in the brain that relates to song learning. If a male finch can’t sing he can’t mate and so no fitness. Females don’t need to sing so females don’t have this part of the brain. when these finches hatch under the influence of testosterone this part of the brain doubles in volumes when the males are learning and developing their songs at the expense of other arts of their brains
sexual preference is under social control and changes can occur in their lifespan e.g in zebra finches
females like red and so red is produced by carotenoids but males need to decide to use carotenoids for immune system so only high quality males can use the red for pigmentation.
In an experiment if males have red rings attached then they are more likely to be chosen by females.
What happens to female offspring if the female has an ornamented father? she will show preference for ornamented males in contrast if females have an unornamented father even if the mother is ornamented they show equal preference for either.
