1. Species diversity refers to the number and variety of species in a given region. It takes into account both the number of species and how evenly abundant they are. 2. There are three main types of species: endemic, exotic, and cosmopolitan. Endemic species are restricted to a particular area while exotic species have been transported by humans. 3. Factors that affect species diversity include speciation, extinction, migration, habitat destruction, and the introduction of invasive species. Speciation occurs through geographic isolation or reductions in gene flow. Extinction can be caused by overharvesting, pollution, and habitat loss.

1. SPECIES
DIVERSITY-Ecology-
Species diversity

2. INTRODUCTION
(Palarca)
Species diversity

3. • Species- Largest group of organisms capable
of interbreeding and producing fertile
offspring.
• Diversity- A state of being diverse or variety.
- A range of different things.
Species diversity

4. SPECIES DIVERSITY
- number or variety of species in a particular region.
Species diversity
- number of different species that are represented in
a given community (a dataset)
-incorporates both the number of species in a
community (species richness)and the
evenness of species‘ abundances.

5. How many species are there?
Species diversity

6. Types of Species
(Estose&Rabongue)
Species diversity

7. 3 Types of Species:
• Endemic species
- is one whose habitat is restricted to a particular
area; often endangered
- differs from “indigenous,” or “native,” (although it
occurs naturally in an area, is also found in other
areas.)
Species diversity

8. 2 Types of Endemic Species:
• paleoendemic
-confined to just one area.
• neoendemic species.
-two populations evolve differently, because they
cannot interbreed with one another, and eventually
they are sufficiently different from one another to be
classified as separate species.
Species diversity

9. • Exotic Species
-is any species intentionally or accidentally
transported and released by man into an
environment outside its present range.
-most severe agents of habitat alteration and
degradation, and major cause of the continuing loss
of biological diversity throughout the world.
• Cosmopolitan Species
-Pertinent or common to the whole world.
-Cosmopolitan distributions can be observed both
in extinct and extant species.
Species diversity

10. Factors Affecting
Species Diversity(Corona)
Species diversity

11. Speciation
-is the evolutionary process by which new
biological species arise.
4 modes:
1. Allopatric- speciation that occurs when biological
populations of the same species become isolated from
each other to an extent that prevents or interferes with
genetic interchange.
Species diversity

13. • Parapatric
– relationship between organisms whose ranges do
not significantly overlap but are immediately
adjacent to each other; they only occur together
in a narrow contact zone.
Species diversity

14. • Peripatric
– formation of new species through evolution.
Species diversity

15. Species diversity

16. • Sympatric
– is the process through which new species evolve
from a single ancestral species while inhabiting
the same geographic region.
Species diversity

17. 2 causes of Speciation:
• Geographic Isolation
– populations were prevented from interbreeding
by geographic isolation.
– rivers change course, mountains rise, continents
drift, organisms migrate.
Species diversity

18. Geographic isolation
Species diversity

19. • Reduction of Gene Flow
– a population extends over a broad geographic
range, and mating throughout the population is
not random. Individuals in the far west would
have zero chance of mating with individuals in the
far eastern end of the range.
Species diversity

20. Species diversity

21. • Extinction
-is defined as “the reduction of a species to such
low abundance that, although it is still present in
the community, it no longer interacts significantly
with other species.
Causes:
Taking for Profit
Hunting and Trapping
Overharvesting
Introduced Species
Destruction of Habitat
Pollution
Species diversity

22. Spotted Visayan Deer
Philippine Eagle

23. • Migration
- is the moving of individuals of a species from one
place to another
• Immigration
- is the migration seen as the settling in one region
(permanently or temporarily) of individuals coming
from another region.
• Emigration
- is the migration seen as an exit of individuals
from one region (to another where they will settle
permanently or temporarily).
Species diversity

24. Positive impacts of alien
invasive species
(Imperial)
Species diversity

25. • Helps to keep the environment in a natural
balance
- an ecosystem which is species-rich is more resilient
and adaptable to external stress than one in which
the range of species is limited.
- In a system where species are limited, the loss or
temporary reduction of any one could disrupt a
complex food chain with serious effects on other
species in that same system.
Species diversity

26. • Provide beneficial products
- tropical rainforests, in particular, have provided
many beneficial products, from natural
medicines to biological control agents for
agriculture.
• Food
- access to a wide variety of species and genes
within those species can be used to meet the
changing needs of the worlds population in many
ways, by using techniques such as selective breeding
crossbreeding or even genetic manipulation.
Species diversity

27. Negative impacts of alien
invasive species
(Salva , Jabol, Visto, Ebcas,Acle)
Species diversity

28. Invasive species
Species diversity
-is an organism that causes ecological or economic
harm in a new environment where it is not native.
Here are some ways invasive species impact native ecosystems:
• Habitat modification
• Compete with native species for resources
• Predation of native species
• Herbivory on native plants
• Bring in pathogens
• Hybridize with natives, leading to loss of genetic diversity

29. • Economic
– loss or reduced efficiency of production.
– the introduction and spread of alien invasive
species can have major implications for trade
which will depend on the policy response of
trading partners.
• Predators
-reduce the population sizes of native species, or
even drive them extinct, because native prey species
may not have evolved defenses against the novel
predators
Species diversity

30. • Genes
- If introduced or spread into habitats with closely
related species, alien invasive species could
interbreed with native species resulting in changes
to the genetic makeup of either species
• Hybridization:
- species' genetic compositions can change
drastically by mating with closely related species,
making the less common species extinct by
hybridization.
Species diversity

31. • Species
- Alien invasive species can influence species diversity,
richness, composition and abundance.
- At the species level, direct effects of alien invasive
species occur through processes such as;
a. Predation
b. Competition
c. Pathogens/diseases
d. Parasite transmission to individual organisms
*eventually leading to population declines and species
extinctions
Species diversity

32. • Habitats
- through their impacts on species and
ecosystem processes, alien invasive species can
result in;
a. Fragmentation
-is the process by which habitat loss results in the
division of large, continuous habitats into smaller, more
isolated remnants.
Species diversity

33. b. Destruction
-is the process in which natural habitat is rendered
functionally unable to support the species present.
c. Alteration
-is a change in land
d. Complete replacement of habitats
*which in turn affects pecies and ecosystem processes.
Species diversity

34. • Ecosystems
-the impacts of alien invasive species at the
ecosystem level include changes to;
a. trophic structures
b. changes in the availability of resources
- water
- nutrients
c. changes in the disturbance regimes.
Species diversity

35. • Social and Health
- a loss of food sources and traditional
medicines may be experienced thereby
compromising not only the health of local people
but also the livelihoods of those dependent on the
collection and sale of such items for income.
Species diversity

36. Measuring Species
Diversity
(Awa & Andrino)
Species diversity

37. • Species Richness
-the number of species that live in a certain
location.
- a count of species, and it does not take into
account the abundances of the species or their
relative abundance distributions.
- only residents are counted
- treats common and rare species with the same
weight
Species diversity

39. Desert Lizard Diversity
Lizard Species Number of
Individuals
Cnemidophorus tesselatus 3
Cnemidophorus tigris 15
Crotophytus wislizenii 1
Holbrookia maculata 1
Phrynosoma cornutum 10
Scleoporus magister 2
TOTAL Individuals 32

40. Desert Lizard Diversity
Lizard Species Number of
Individuals
Cnemidophorus tesselatus 3
Cnemidophorus tigris 15
Crotophytus wislizenii 1
Holbrookia maculata 1
Phrynosoma cornutum 10
Scleoporus magister 2
TOTAL Individuals 32
Species Richness

41. Species of Dogs
Species diversity

42. • Relative abundance
- also known as “Heterogeneity of Species”
-is the number of individuals of each
species.
-refers to how common or rare a species is
relative to other species in a defined
location
Species diversity

43. Desert Lizard Diversity
Lizard Species Number of
Individuals
Cnemidophorus tesselatus 3
Cnemidophorus tigris 15
Crotophytus wislizenii 1
Holbrookia maculata 1
Phrynosoma cornutum 10
Scleoporus magister 2
TOTAL Individuals 32

44. Lizard Species Number of
Individuals
Cnemidophorus tesselatus 3
Cnemidophorus tigris 15
Crotophytus wislizenii 1
Holbrookia maculata 1
Phrynosoma cornutum 10
Scleoporus magister 2
TOTAL Individuals 32
Species Relative
Abundance
Desert Lizard Diversity

45. Formulas:
• Shannon Wiener Index:
s
H’ = -∑pi logepi
i=l
H’ = Value of SW diversity index.
pi = Proportion of the ith species.
loge = Natural logarithm of pi.
s = Number of species in community.
Species diversity

46. • Shannon-Wiener diversity function
H' = - (pi) [ln(pi)]

H’ = Shannon-Wiener index of species diversity
s = number of species in community
pi = proportion of total abundance represented
by ith species
Species diversity

47. Hotspots for Species Diversity
Species diversity
• The hottest spots for species diversity
are tropical rainforests.
Tropical rainforests comprise of only 7% of
all land on Earth, yet are home to nearly 50% of
all the species on Earth!