This document discusses the history, levels, and estimates of biodiversity. It outlines that biodiversity is classified into 4 main levels: genetic, species, ecological, and landscape diversity. It also estimates that the total number of species on Earth ranges from 5-50 million, with most insect species yet to be discovered. Methods for estimating total species numbers include extrapolating from known vs unknown species ratios, relationships between body size and diversity, and rates of new species discovery over time.

1. BIODIVERSITY:
HISTORY, LEVELS AND
ESTIMATES
PAPER- 401
Presented by:-Yunus khan
MSc. IVth sem. Final year
Submitted to:- Prof. Dr. S. Sundaramoorthy
Department of Botany,
JNV University jodhpur.

2. BIODIVERSITY

3. BIODIVERSITY : HISTORY
■ Species concept:- it is very old. One spp. Is
different from another. Its talk about variation in
among.
■ DARWIN’s CONCEPT:
■ Proposed theTheory Of Evolution By Natural
Selection.
■ Every individual is a variant in the population. Its
talk about variation within, except rare twins.
■ Whittaker 1950- was give α,β,γ diversity.
■ Dasmann 1968 –firstly used term Biological
diversity.

4. ■ Lovejoy & team (1980): introduced the term
Biological diversity to the scientific community in a
book. Biological diversity= number of species.
■ It is rapidly became commonly used.
■ Norse & McManus organized, Conference(1981) US
Strategy on biological diversity.
■ Walter G. Rosen (1985) - coined the word Biodiversity
, He abbreviated the Biological diversity to
Biodiversity.
■ Laura Tangley 1985- the term first appears in the
article , “A new plan to conserve the Earth’s Biota.”
■ the word “Biodiversity ” is first appeared in the book
(1988).

5. ■ Norse & McManus
■ Later, Norse et al in 1986 , Biodiversity was described under 3
levels:
Biodiversity
Genetic Species Ecological
Biodiversity
Genetic
Diversity
Species
Diversity
LEVELS OF BIODIVERSITY

6. Conti…
■ Ecological diversity = ecosystem diversity.
■ Harper & Hawksworth - Biodiversity classified into 3 levels:
■ Eldredge (1992):
Biodiversity
Genetic Species Ecological
Biodiversity
Genealogical
diversity
Organism
diversity
Ecological
diversity

7. ■ Geniological diversity = Genetic
diversity.
■ Organism diversity - Phenotypic
diversity
■ Ecological diversity
■ A 4th diversity is also included-
■ Landscape diversity- Because diversity
forming a unit in remote sensing acc.
Larger area diversity assessment.

8. So levels of Diversity are only 4
• Genetic diversity
• Species diversity
• Ecological diversity
• Landscape diversity

10. Species diversity

11. Ecological diversity

12. Landscape diversity

13. Meaning/Definition
■ Biodiversity meaning- the variability
among living organism from all sources
including Intralia, terrestrial, marine &
other aquatic systems and the ecological
complexes of which are part, living
organism.
■ IUCN & UNEP (1992)- defined biodiversity
as the “totality of genus, species &
ecosystem in a region.”

14. Estimates
■ Saying biodiversity as guess/assume is not right it
is only estimated.
1. Hells et al 1993 –
■ One kind of estimation – “Species area relationship”
■ use the higher/lower range from 5-50 million spp.The no.
is give the function-
𝑺 ∝ 𝑨 𝒁 ( z⟹ 0.1 ---- 0.4)
No. of Spp. ∝ No. of Area
■ Grassle & Maclolee – using this estimate
Deep sea has 13.6M spp. Are conserved
1.76M are known and identified rest are unknown.

15. Conti…
2. Known to Unknown Concept
■ It is estimated that In tropical region every
birds/mammals has 2 distinct relatives are present.
■ Spp. Known to unknown ratio is 1:3
■ Hodkin and Casson –Application
From the study area – 62.5% bugs spp. Unknown
Considering 7.5 – 10.7M bugs (global diversity insects
in bugs) unknown.
Estimate of bugs= 1.84 – 2.5M insects spp. Is Known

16. Conti…
3. Assumption in body size
■ Empherical rule-
10 fold reduction in body size = 100 fold increase in
no. of spp.
If animal mean size is 0.2mm in length = 10M no. of
spp.
4. Rate of discovery-
■ The rate of discovery of new spp. In each group.
■ ±2400 new insects are reported in every year.
■ Project forward- thus calculation of Project forward
leads to 6 – 7M spp.

17. Conti…
5. Torry Erwin – Kill em count em experiment.
■ A single spp. Of tree Luebea Seemannii, he found
<1100 spp. Of beetles.
■ He first estimated = 160 of those spp. Specialized
to the canopy.
■ In this 2/5 of spp. represent beetles of total insect
diversity = 400 (160x5/2) spp. Specialized to the
canopy of a single tree.
■ So the estimated range of tropical Arthropods is
about 30 – 50M spp. On earth.

18. Estimated and described species diversity in
different group by pie chart.