Parasitism has evolved over time as parasites adapt to their hosts. Parasites like malaria originated in primates in Africa and later transferred to humans. Malaria is caused by Plasmodium parasites transmitted via mosquito bites and Plasmodium falciparum is thought to have evolved from gorillas to infect humans around 50,000 years ago. Parasites continue evolving in response to hosts and their environments.
3. Evolution of Parasitism
A parasite is an organism that lives on or in a
host organism and gets its food from or at the
expense of its host
The parasite lives on or in the body of the host. A
few examples of parasites are tapeworms,
īEctoparasites
ī These live on, rather than in their hosts.eg ticks
fleas mosquitos
īendoparasites
īThese are internal parasites live inside the host
body eg bacteria protist tapeworm
ī
4. Parasitism
īŽ is a type of symbiotic relationship, or
long-term relationship between two
species, where one member, the
parasite, gains benefits that come at the
expense of the host member without
killing the host organisms
īŽ
5. īŽ All organisms have their own parasites
parasites are host restricted
īŽ May have copmplex life cycle with
different stages in different
īŽ Lice that infect human have different
type of hook as compared to infect
another animals.
īŽ it prefer human hair as compared to
another animal hairs
6. īŽ Parasitism is composed by three
subsystems: the parasite, the host, and
the environment
īŽ Some parasite species that infect
humans were inherited from pre-
hominids, and were shared with other
phylogenetically close host species, but
other parasite species were acquired
from the environment as humans
evolved. Human migration spread
inherited parasites throughout the
globe.
7. Evolutionary ecology
īŽ Parasitism is a major aspect of
evolutionary ecology; for example,
almost all free-living animals are host to
at least one species of parasite.
Vertebrates, the best-studied group, are
hosts to between 75,000 and 300,000
species of helminths and an uncounted
number of parasitic microorganisms.
8. Mesophthirus engeli, a louse-like ectoparasite on
damaged mid-Cretaceous dinosaur feathers[
9. Trichomonas
īŽ Parasitism is hard to demonstrate from
the fossil record, but holes in the
mandibles of several specimens of
Tyrannosaurus may have been caused
by Trichomonas-like parasites.
10. louse-like ectoparasite
īŽ A louse-like ectoparasite, Mesophthirus
engeli, preserved in mid-Cretaceous
amber from Myanmar, has been found
with dinosaur feathers, apparently
damaged by the insect's "strong
chewing mouthparts
11. Parasites evolution
Parasite evolution refers to the heritable
genetic changes that a parasite
accumulates during its life time, which can
arise from adaptations in response to
environmental changes or the immune
response of the host. Because of their
short generation times and large
population sizes, parasites can evolve
rapidly.
12. īŽ Host and parasites evolve 50 million
years ago before the evolution of man
īŽ Virulence described as the capacity of
parasite to harm a host
īŽ Evolutionry determined virulence in term
of host fitness
īŽ The capacity for a parasites to reduce a
fitness host and directly killing capacity
varying from
13. Adaptation of parasitism
īŽ Parasites are adapted to get
maximum benefits ftom their host
do not kill them.
īŽ Tapworm has strong sucker and
hook for attachment to the lining of
small intestine and large area for
absorption of water.
14. Co evolution
īŽ Any change take place in human
parasites take place in parasites to well
adapt in enviornment
īŽ Anareobic respiration in internal
parasites.
īŽ Loss of digestive organ and loss of
wings
īŽ Devolpment of adhesive organs
17. parasites are extraordinarily diverse. Even
closely related parasites may behave very
differently, infecting different host species,
causing different pathologies, or infecting
different tissues.
Example
Escherichia coli bacteria, a typically harmless
inhabitant of the human gut, can, in different
forms, cause diarrhea, intestinal bleeding,
urinary tract infections, kidney bleeding,
meningitis, and other diseases .Underlying this
diversity is evolution.
19. Define
īŽ a human disease that is caused by
sporozoan parasites (genus
Plasmodium) in the red blood cells, is
transmitted by the bite of anopheline
mosquitoes, and is characterized by
periodic attacks of chills and fever.
īŽ any of various diseases of birds and
mammals caused by blood protozoan
20. Malaria situation in pakistan
īŽ Pakistan has a population of 180 million
inhabitants of which 177 million are at
risk of malaria. With 3.5 million
presumed and confirmed malaria cases
annually. ... Vivax malaria still
dominates the transmission though
significant rise in the more lethal form
falciparum is observed in Balochistan
and Sindh.
21. Situation in pakistan
īŽ Karachi saw about 1873 malaria cases
in 2019
īŽ In Pakistan, malarial incidence reaches
its peak in September. 1000 million
people have died from Malaria since
Pakistan came into being till December
2012.
22. Mostly infected country
īŽ n 2019, the region was home to 94% of
all malaria cases and deaths.
īŽ In 2019, 6 countries accounted for
approximately half of all malaria deaths
worldwide
īŽ Nigeria (23%), the Democratic Republic
of the Congo (11%), United Republic of
Tanzania (5%), Burkina Faso (4%),
Mozambique (4%) and Niger (4% each).
23. Origion of plasmodium
īŽ Plasmodium falciparum arose in humans after the
acquisition of the parasite from a gorilla.
īŽ Plasmodium vivax is a bottlenecked parasite lineage
that originated in African apes.
īŽ Recent molecular studies have found evidence that
human malaria parasites probably jumped onto
humans from the great apes, probably through the
bites of vector mosquitoes.
īŽ Malaria seems to have been known in China for
almost 5,000 years.
24. īŽ Human malaria likely originated in Africa
and coevolved with its hosts,
mosquitoes and non-human primates.
Malaria protozoa are diversified into
primate, rodent, bird, and reptile host
lineages. Humans may have originally
caught Plasmodium falciparum from
gorillas.
25. īŽ Plasmodium parasites enter the body
through the saliva of female mosquitoes
from the genus Anopheles. These
mosquitoes primarily inhabit the tropical
and subtropical parts of the world.
28. Evolution of malaria
īŽ Plasmodium falciparum is the only
parasite from this group that has
successfully adapted to transfer from
gorillas to infect humans, and
subsequently spread all over the world.
īŽ Scientists discovered that the
evolutionary lineage leading to
Plasmodium falciparum emerged
50,000 years ago