The document discusses the relationship between ecology and evolution, emphasizing how seasonal changes affect gene expression and adaptation in organisms. It highlights the influence of seasonal variations on human health, including immune function and disease prevalence, and explains how migration leads to genetic diversity and evolutionary changes. Additionally, it examines the impact of climate change on species and the evolution of human digestive systems in response to food availability.

1. Ecology and evolution

2. Name Nizad sultana
Submission date 13-08-20

3. •Ecology shapes evolution

4. Ecology and evolution
• Ecology is the study of interaction between an organism and
it’s environment.
• Evolution is the change that occur in characteristics of
organism over time:-
• It may be change in form and behavior of organism over
generation.
• It may be genetic change in population of organism over
time.

5. • Seasonality defined as variations that occu specifically at
specific intervals that is less than year may be quarterly
weekly or fot monthly.
• There are various factors that cause seasonality that are
vecations as well as vecations along with periodic repetitive,
morever regular as well predictable patterns in levels of a
time series.

6. Adaptation
• Adaptaion is actually is characteristics that determined genetically
that then improves ability of organism to reproduce as well as
increase its ability to survive in particular determined environment.
• Three types of adaptation that occur in response to variations are :-
• Behavioral physiological or morphological adaptations
• In response to seasonal changes occur in environment.

7. Genetic variations
• It refers to diversity that found in frequency of genes. Genetic
variation is basically used to explain basic variations that comes in
DNA sequence in geneome of us.
• Population
• A group of individuals of same species that live in same area and
interbread.
• Gene pole
• Consists of all the gene of in all individuals making up population.

8. Gene regulation and seasonal effect
• One important factor of environment that has tremendous effect on
gene regulation is seasonal variationswell-documented effect is
seasonal variations
• Changes that comes in regulation of gene are directly related to
seasonal effects for example photoperiod in animals and plants.
• Much research on effects that these seasonal variation have in many
animals including human only focus on these genes sub-set or we can
say cluster of these genes while failed to identify those genes which
express themselves according to change in season.

9. There are many health conditions tht are being affected by
changes in seasons, including cardiovascular disorders,
asthma, depression , bipolar disorder, migraine
diabetes,schizophrenia etc.

10. Seasonality along with infection rate
• Environmental changes also have effect on outbreak if many
infection as well on their rates like
• influenza
• Syncytial virus for respiratory disorder also deficiency of vitamin D
mainly caused by genes that identity changes in ultraviolet rays that
comes seasonaly.
• Thus expression level of these change in response to season
potentially shed some light mechanisms that seems to drive these
conditions.

11. • At first it was seems to be absurd that seasons have any effect on gene
expression but recent studies has proven that seasons have a massive
effect on how our genes function within our bodies.if we think on it
more than we come to know that there are deep molecular changes that
comes in us due to these changes in seasons.
• Trees loses all their leaves while many animal also grow their coats of
winters while bird also prepare for their long journey to south.All of
us are primal genetic code then why our genes would not vary with
seasonality.

12. Experiment
• study was done at University of Cambridge a experiment
was done in which more than sixteen thousand people were
tested from all over the world in order to see how genes can
be vary with variations in seasons
• Samples were taken that of bloodas well other tissues
samples were taken this work was continue for about a year
about twenty two thousand genes were completely
analyzed.result of study was that found to be nearly a
quarter of analyzes genes shows signs of variation as well its
means that function of genes changed when season change.

13. Gene of immune system
• Genes in specific that associated with immune system
inflammation that occur more during winter season showing
increase function of gene during these months. This provide
significant site into process of increase of infections of viruses
that increase in coincidence with cold months. Than come
function of our geOur that involves in increasing immune
function due to evolution during these cooler months so that we
can fight with illness cause by cold like cough flu fever etc.

14. Example of Immune system
• Changes that comes in our genes these mirror those change
of seasons are not at all flukes.
• Experiments show these changes comes in genes based on
variations in environment where we are living as seasons
vary area to area.
• Genes that are associated with immunity as well
inflammation become active in months of December to
February among People that are living in northern areas
while active in June to August among people lives in
southern areas.

15. • People that lives in warm or cold climate that are constant
patterns alsovaries as well. People lives close to
aquatorial area climate in these areas usually stays at
steady. Year round exhibit variation in genes in rainy
season also when infection become more profound more
ever disease that born due to mosquitos like malaria
become more rampant. On other hand , people that lives in
cold climate like in Iceland have little variations or even
no seasonal variation that comes in function of gene.

16. Seasonal variation as a tool
• seasonal variation that comes in function of genes act as tool for survive,
there are clear evidence about increased function that also have
contribution towards seasonal flare ups of diseases includes heart disease,
diabetes type one also of arthritis.
• Especially in U. K medical community reports significant increase of
above mentioned diseases occur more during cold months from December
to February when our immune system becomes weak.
• Microbiome in gut can play a tremendous role in appearance of these
diseases when these flare ups because these micro biome changes
seasonally as well.it seems to be impossible to just take one cause of these
diseases however variation in genes seasonally have important role.

17. Change in season an advantage to human
• Evolutionarily, seasonal changes that occur in gene
functionuis basic advantage to orgnisms heltumans to fight
against diseasis as we need as well help humans to in
conservation of energy this is done by varying genes
function by modifying metabolic activity during colder
months.

18. However some of variations of genes have no longer relevant
because ability of us as we can alter our climate by means of
our access to food year arroundly some of these changes are
highly appreciated still . You can thank your genes in next
season of flu as well of cold rolls around you can also
manage to stay healthy.

19. Seasonal changes effect on organisms
biology
• Days , nights around world for a brief period close about twelve hours
day as well night.
• As our earth continue its revolution around sun it effects days length
as these become shorter while nights become lengthen, these change
become more prominent in high latitudes, but it will become none
existent at equator.
• The change in amount of light that comes as basic signal to
organisms.
• Some organisms that lives at high lattitudes these changes can bring
profound effect on biologyof these organisms mainly on their
reproduction which should be carefully on time.

20. Some examples
• For example,in winters there are long days Siberian hamsters have its
testes increase upto seventeen times than their size during summers
when days are short.
• There is available evidence about birds that lives near source of
artificial light starts singing in order to attract their mates also for
laying eggs, earlier in the spring than their counterparts in places that
remain dark at night.
• There is also evidences that there is increase in suicides as seasonal
peaks shows there is rapid increase occur in summer morever birth
rates also increase in spring as well as in summer seasons

21. Effect of season change on harmone
• Strongest evidence of seasonality in humans is example of seasonal
affective disorder, SAD. Its victims suffer from depressive episodes that
relates to seasons commonly begins in late fall or from early winter, while
remitting in summer or spring.
• People who are suffering from this disease secreted a well known
hormone called melatonin during nights of winter for longer period also
during nights of this fluctuation in harmon also present among thoes
mammals that have behavioral variations seasonally. However, production
of melatonin in humans tht is responsible for regulating sleep awake cycle
is called melatonin that is also known as hormone of darkness, dis not show
variations with season.if we talk about people living at higher latitudes
SAD affects about ten percent of population.

22. Role of photoreceptors
• Receptors of light in eye retina like cones as well as rods a third one
is retinal ganglion cell that is photosensitive these pass information
that are other than visual signals used to reset rhythms that are
circardium.
• People that have long natural sleep cycle called to be night owls while
, people that tend to rise up early known as morning larks.

23. How variations leads to evolution
• With changes in climate this brings changes in certain factors
like temperatures also rises droughts increases patterns of
precipitation also occur plants as well animals beings
modification in order to keep p1ce with changing environment so
this leads to evolution.
• Many biologists observed salmon as well squirrel developed at
accelerated pace cause them to reproduce at a younger age.
• early summers have profound effect on flowers caused them to
bloom early in year.
• Same case with corals are forging in order to make new
relationships with microscopic algae so that they can survive in
changed warmer hence more acidic sea environment.

24. Warmer climate and diseases
With changes that are occurring in surrounding environment like climate is
becoming warmer day by day evolutionary changes also expected in many
species including humans.
• Climate change also alter workings activities in our bodies in significant
ways as well will cause noticeable change in organisms appearance.
• Inside our body:-
• Warmer climate brings Malaria as well as Nile virus along with many
other diseases for a long period these are being confined to tropical areas
then will increasingly spread into temperate areas so result would be
people livespecially developed areas like U.S. as well as other nations soon
will become exposed to following illnesses as a result due to all these
factors our immune function will forced in order to evolve new strategies
of defense. That will also cause other diseases.

25. • Popular disorders of blood anemia along with Thalassemia
suddenly arise then these continue their existence because of fact that
they tend have side effects that are beneficial.
• malarial resistance
• New disorders or may be these appear soon if this malarial infection
moves to areas that are highly populated like America in Asia as
well as in Europe.

26. Human digestive system evolution with
respect to availablity of food
• In similar way if we talk about evolutionary changes occur due to variations in season
our system of digestion evolve as food availability changes in external environment
due to seasonal change .
• Ability for digesting milk as well other milk products in adult also evolved among
certain groups in Middle East as well in North Aafrica in those who began to raise
cattle. Furthermore next generations that will come evolve even better well formed
abilities foro tolerating fat as well sugar in milk.
• Morever change in diet also brings different change in certain microbiome ththa live
in our guts like certain bacteria Changing diets will also initites changes in
microbiomes bacteria along with other microorganisms that live in our guts these
have role in keeping us healthy. Vegetarians have different microbiome present as
compare to non vegetarian these changes that evolve in these microbiome thave
profound exaggerated for prolong time it would be costly to raise livestock.

27. Migration due to seasonal changes
• One of important cause of evolutionary changes that brings new
population is blending of genes occur due to migration. Migration
is process in which organisms moves from 9ne area to another in
order to settle temporary or permanently due to different reasons.
• Consequence of migration 9n large scale in form of blending of
genes. When matting occur between people that belongs to two
different populations then they reproduce intermingling of in their
genes takes place then children will have combination of
different traits that are not being seen in neither of parents nor in
populations from which they belong to for example their dark
skin as well blue eye color of Cape islanders that comes when
interbreeding Occur between Portuguese & Africans.

28. Effect of gene flow
• Result of migration as well gene flow due to which mixing
of ge’es occur is simmilarties in color of human skin.
• DiffereNce in skin color in various population of humans
come as result of natural selection While pigment that is
present eumalanin gives dark color to skin not only this it
also protect skin against harsh rays of sunlight. However if
concentration of eumalanin increase vitamin D production
decreases that results in weak bones.

29. • We can say from many thousand of year populations of humans
evolve different levels of pigmentation of skin that vary when these
spreaded across whole map, so natural selection actually balance cost
of too much harmone production in population that can cause
deformation 8n bones indirectly as well to have very little
concentration lead to skin cancer also brings birth defects.
• So result will be that color of skin match closely to sunlight intensity
in different areas in world dark near equator while light near poles.

30. •Thank you