PEE - STATE OF PHILPPINE BIODIVERSITY AND ITS EXTINCTION

Biodiversity

The variety of all living things; the different plants, animals, fungi and microorganisms, the genetic information they contain and the ecosystems they form.

Extinction

The disappearance or dying out of a species due to environmental factors like habitat destruction, climate change, natural disasters, or overuse by humans.

Invertebrates

Animals without a backbone, with no bones at all. Includes spiders, worms, snails, lobsters, crabs, butterflies, etc.

Deforestation

Tropical rainforests, home to a huge variety of species, are being destroyed.

Endemic species

Species that are only found in a specific geographic area and do not occur naturally anywhere else in the world.

Biodiversity origin

Comes from “bio” meaning life, and “diversity” meaning variability.

Types of biodiversity

• genetic diversity

• species diversity

• ecosystem diversity

Genetic diversity

Variety of genes within a species.

Different populations have different genetic compositions.

To conserve genetic diversity, different populations must be preserved.

Species diversity

Variety of species within a habitat or region.

Rainforests and coral reefs have many species; salt flats or polluted streams have fewer.

Includes information on endemic families in Australia.

Invertebrate importance

99% of all animal species are invertebrates.

Roles: pollinators, recyclers, scavengers, food sources.

Mammals make up less than 1% of animal species.

Ecosystem diversity

Variety of ecosystems in a place.

Ranges from large areas (forest) to small (pond).

Megadiversity

Describes countries with very high biodiversity.

Global species count

Approx. 8.7 million species on Earth.

6.5 million on land, 2.2 million in oceans.

7.2 million species still undiscovered.

IUCN Red List status

Over 166,000 species listed.

More than 46,300 threatened with extinction.

Philippine species status

More than 52,177 described species.

Half are endemic.

The Philippines is one of 17 megadiverse countries.

Has 60–70% of the world’s biodiversity.

Top 10 globally in endemism.

Endangered

Seriously at risk of extinction

Examples – endemic

Tamaraw – Philippine bovine from Mindoro.

Philippine eagle – found on Luzon, Samar, Leyte, Mindanao.

Examples – endangered

Philippine eagle – fewer than 400 pairs in the wild.

Hawksbill sea turtle – threatened by habitat loss and coral reef degradation.

Examples – extinct

Visayan warty pig – example shown.

Cebu dwarf buffalo – fossil dwarf buffalo identified in 2006.

Relationship between health and biodiversity

Human health depends on ecosystem services: fresh water, food, fuel.

Loss of biodiversity disrupts resources and ecosystem functions.

Main human-caused threats include habitat loss, climate change, and resource extraction.

Disease and biodiversity loss

Biodiversity loss increases infectious disease risk.

Linked to outbreaks such as SARS, Ebola, COVID-19.

Mass extinction

Occurred at specific times in history.

Shaped biodiversity by eliminating large numbers of species.

How scientists identify mass extinction

Clues in the fossil record and rock composition changes.

Adjacent rock layer shifts indicate catastrophic events.

Natural causes of extinction

• volcanic activity

• asteroid impacts

• changes in Earth’s carbon cycle

• changes in sea level

• tectonic uplift

Pre-colonial period

Extinctions were mainly due to natural causes like climate shifts and geological changes.

Examples:

• woolly mammoth

• Celebochoerus cagayanensis

Colonial period

Spanish and American colonizers caused:

• habitat destruction

• deforestation

• introduction of non-native species

Examples:

• eagles and cloud rats overhunted

Modern period

Rapid industrialization, urbanization, monocropping, chemical use.

Climate change worsens impacts.

Invasive species proliferate.

Examples:

• passenger pigeon extinction

• Tamaraw threatened by ranching and urban expansion