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Lesson 1: THE EARTH THROUGH TIME

4.57 billion years ago: formation of the earth

THE BIBBGANG THEORY (FATHER GORGES LAMAITRE)

-          14 billion y/a wala pang kahit ano kundi isang maliit na point called “singularity”

-          Singularity have high tep and densed.

-          Dumating si God at nagkaroon ng explosion.

-          Dahil sa explosion nagkaroon ng “element of light” which are the hydrogen, helium, lithium, and beryllium.

-          These elements of light are fuel for formation of stars.

-          EVIDENCES OF BIGBANG:

o   1. Redshift: pagsukat ang frequency ng wave of lights coming from the stars.

o   They discover na yung frequency ng mga stars ay nagdi decrease meaning lumalayo yung mga stars.

o   2. Cosmic Microwave Background (CMB): heat from the earth na nagpaapatunay na the earth was onced high temp.

GEOLOGICAL TIME SCALE

-          Fossil record: fossdil sa rocks.

o   Carbondating: detects how old an stone.

4 EONS:

-          Hadean

-          Arhcean

-          Proterozoic (precombrian super eon)

-          Phanerozoic

1.      HADEAN EONS (4.54 – 4.0 Ga)

-          From Greek word “hades” means God of underworld.

-          Earth is constantly bombarded by asteroids.

-          (4.4 Ga) theia collides with earth:

o   Pumaling yung earth.

o   Ito yung reason bat nagkaroon ng Moon.

-          Zircon crystals: survived from this period.

2.      ARCHEAN EONS (4.O-2.5 Ga)

-          Stromatolites: oldest fossil (3.48 Ga)

-          Formation of large continents.

-          Cratons: remnants of archean continents.

-          100,000 x less 02 than today

-          Abundance of CO2 and CH4

-          Life was unicellular

3.      PROTEROZOIC EONS (2.5 Ga-541 Ma)

-          Begin with grand increase in oxygen generated by cyanobacteria with photosynthetic capabilities.

-          O2 was 1^st absorbed by oceans.

o   ocean eventually became saturaded so oxygen entered the atmosphere.

-          Banded ion formation (BIF’s): iron oxides.

4.      PHANEROZOIC EONS (541 Ma – TODAY)

1.      Paleozoic Era (541 - 252 MYA)

A.     Cambrian Period (541 - 485 MYA):

o   Cambrian Explosion: Rapid diversification of life.

o   First arthropods, mollusks, and early vertebrates appear.

B.      Ordovician Period (485 - 443 MYA)

o   First land plants emerge.

o   Marine invertebrates dominate.

o   Ends with a mass extinction caused by glaciation.

C.     Silurian Period (443 - 419 MYA)

a.      First jawed fish evolve.

b.      First terrestrial arthropods appear.

c.      Coral reefs begin to form.

D.     Devonian Period (419 - 359 MYA):

a.      Known as the "Age of Fishes" due to fish diversification.

b.     First amphibians evolve

E.     Carboniferous Period (359 - 299 MYA):

a.      Divided into Mississippian and Pennsylvanian Epochs.

b.      Large coal forests form.

c.      First reptiles evolve.

F.     Permian Period (299 - 252 MYA):

a.      Formation of Pangaea.

b.      Reptiles and early ancestors of mammals dominate.

c.      Ends with the Permian-Triassic Extinction, the worst extinction event in history, wiping out about 96% of species.

C.     Mesozoic Era (252 - 66 MYA)

G.    Triassic Period (252 - 201 MYA):

a.      First dinosaurs and mammals appear.

H.    Jurassic Period (201 - 145 MYA):

a.      Dinosaurs dominate the land.

b.     First birds appear.

c.      Pangaea begins breaking into Laurasia and Gondwana.

I.      Cretaceous Period (145 - 66 MYA)

D.     Cenozoic Era (66 MYA - Present)

J.      Paleogene Period (66 - 23 MYA):

Paleocene Epoch (66 - 56 MYA):

a.       Mammals rapidly diversify.

Eocene Epoch (56 - 34 MYA): First primates evolve, early whales and bats appear.

Oligocene Epoch (34 - 23 MYA): Grasslands expand, and modern mammal ancestors appear.

K.    Neogene Period (23 - 2.5 MYA):

Miocene Epoch (23 - 5.3 MYA): Early hominins (human ancestors) appear.

Pliocene Epoch (5.3 - 2.5 MYA): First recognizable human ancestors (Australopithecus), Ice Ages begin.

L.     Quaternary Period (2.5 MYA – Present):

Pleistocene Epoch (2.5 MYA – 11,700 YA):

a.      Ice Ages occur.

b.      Homo sapiens evolve (~300,000 years ago).

Extinction of megafauna like mammoths.

c.      Holocene Epoch (11,700 YA - Present):

d.      Rise of human civilization.

Lesson 2: MECHANISM OF EVOLUTION

The origin of species (1859) by Charles Darwin: the beginning of evolutionary biology.

Evolution: change in characteristics of a species over several generations.

-          Evolution is now understood genetically, mutations generate new traits which can be passed on to offspring if favorable.

DEVELOPMENT OF EVOLUTIONARY THOUGHT

1.      ARISTOTLE 350 BCE

-          Species are identical.

-          They can be arranged hierarchally.

2.      GEORGES-LOUIS LECLERC, COMTE DE BUFFON 1749 AD

-          As the species change they migrate to another environment resulting to their distribution.

3.      CHARLES DARWIN 1974

-          Species evolved from one common ancestor.

4.      JEAN BAPTISTE LAMARCK 1809

-          Species evolved from an existing species through environmental forces. Traits can be passed to the next generations.

5.      CHARLES LYELL 1830

-          All changes in the environment are uniform and gradual.

6.      BALFRED RUSSEL WALLACE 1859

-          Species evolved from the process of natural selection which cause variations within the population.

THEORIES ON EVOLUTION OF ORGANISMS

A. Jean-Baptiste Lamarck

1. Theory of Acquired Characteristics

   • Also known as the Theory of Inheritance of Acquired Characteristics or "Soft Inheritance."

   • Organisms that experience modifications during their lifetime can pass these acquired traits to their offspring.

2. Theory of Use and Disuse

   • Body parts that are regularly used become stronger and more developed (hypertrophy).

   • Body parts that are not used weaken or disappear over generations.

3. Theory of Need

   • Environmental changes create new needs for survival.

   • Organisms develop new traits to adapt to these needs.

B. Charles Darwin

1. Survival of the Fittest

   • Organisms that are best adapted to their environment are more likely to survive and reproduce.

2. Descent with Modification

   • Species change over time and descend from common ancestors.

3. Natural Selection

   • Individuals with advantageous traits are more likely to survive and pass on their traits to offspring.

   • This process drives evolution over generations.

4. Artificial Selection

   • Humans selectively breed organisms to enhance desirable traits, such as breeding crops for better yield or animals for specific traits.

MECHANISM OF EVOLUTION

1. Natural Selection: Organisms with advantageous traits are more likely to survive and reproduce, passing those traits on.

2. Genetic Drift: Random changes in gene frequencies, especially in small populations.

3. Gene Flow: Movement of genes between populations through migration and interbreeding.

4. Mutation: Random changes in DNA that create new traits or alleles.

5. Non-Random Mating: Mating based on preferred traits, such as in sexual selection.

Lesson 3: EVIDENCES OF EVOLUTION

1.  Direct Observation: We can see evolution happening in real life, like bacteria becoming resistant to antibiotics or new species forming.

2.  Homology: Similar body structures in different species (like the wings of bats and arms of humans) show that they share a common ancestor.

3.  Vestigial Structures: Body parts that don’t seem to have a function anymore (like the human appendix) are leftover from ancestors.

4.  Molecular Homology: The similarity in DNA or proteins between species suggests they have a common origin.

5.  Fossil Record: Fossils show how species have changed over time, with older fossils showing simpler life forms and newer ones showing more complex ones.

6.  Biogeography: The distribution of species around the world supports evolution. For example, species on islands are different from those on nearby continents, showing adaptation to their environment.