The Origins of Life <ul><li>The oldest fossils came from the ocean shallows </li></ul><ul><ul><li>Cyanobacteria:  aquatic,...
Abiogenesis <ul><li>Scientists propose that simple molecules randomly combined and separated.  </li></ul><ul><li>Larger, m...
Oxygen and Evolution <ul><li>First organisms were simple  heterotrophs </li></ul><ul><ul><li>Rely on consuming compounds t...
Oxygen <ul><li>O 2  important  </li></ul><ul><ul><li>because reactions using 02 allow organisms to use chemical energy mor...
Theory of Evolution <ul><li>Many views on how life started  </li></ul><ul><li>This is a broadly accepted theory in the sci...
<ul><li>Over millions of years natural selection resulted in the variety of life we see today </li></ul><ul><li>Most scien...
Scientists theorize… <ul><li>Single celled organisms evolved from independent existence to life in colonies  </li></ul><ul...
Ocean Zones <ul><li>Water portion  </li></ul><ul><li>pelagic </li></ul><ul><ul><li>Neritic:  between low tide & edge of co...
<ul><li>The Sea floor </li></ul><ul><li>Benthic zone </li></ul><ul><ul><li>Littoral:  intertidal </li></ul></ul><ul><ul><l...
Marine Lifestyles <ul><li>Marine scientists classify life into 3 lifestyles: </li></ul><ul><ul><li>Plankton, nekton, benth...
<ul><li>Nekton:  swimmers </li></ul><ul><ul><li>Examples? </li></ul></ul><ul><ul><li>Most are vertebrates </li></ul></ul><...
<ul><li>Benthos:  live on or in the bottom, can move about or be sessile. </li></ul><ul><ul><li>Epifauna:  animals that li...
Upcoming SlideShare
Loading in...5
×

The Origins Of Life

750

Published on

From the marine science perspective: a description of how life began, evolution, oxygen and evolution, ocean zones and marine lifestyles.

Published in: Education, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
750
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
35
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Transcript of "The Origins Of Life"

  1. 1. The Origins of Life <ul><li>The oldest fossils came from the ocean shallows </li></ul><ul><ul><li>Cyanobacteria: aquatic, photosynthetic </li></ul></ul><ul><ul><li>3.5 billion years old </li></ul></ul><ul><li>Scientists don’t know how life began </li></ul><ul><ul><li>Many hypotheses proposed </li></ul></ul>
  2. 2. Abiogenesis <ul><li>Scientists propose that simple molecules randomly combined and separated. </li></ul><ul><li>Larger, more complex molecules fromed </li></ul><ul><li>When these were able to reproduce, life was formed </li></ul>
  3. 3. Oxygen and Evolution <ul><li>First organisms were simple heterotrophs </li></ul><ul><ul><li>Rely on consuming compounds to obtain energy </li></ul></ul><ul><li>Autotrophs appeared (3-3.5 bil yrs) </li></ul><ul><ul><li>Can create organic chemical energy from inorganic compounds </li></ul></ul><ul><ul><li>Increased atmospheric O2 from 1-21% by breaking C0 2  0 2 </li></ul></ul>
  4. 4. Oxygen <ul><li>O 2 important </li></ul><ul><ul><li>because reactions using 02 allow organisms to use chemical energy more efficiently </li></ul></ul><ul><li>Biologists theorize that O 2 allowed the development of mitochondria </li></ul><ul><ul><li>Cellular organelles that use O 2 to process energy </li></ul></ul>
  5. 5. Theory of Evolution <ul><li>Many views on how life started </li></ul><ul><li>This is a broadly accepted theory in the scientific community </li></ul><ul><li>Natural Selection </li></ul><ul><ul><li>Organisms with characteristics that favor survival pass those characteristics to offspring </li></ul></ul><ul><ul><li>Originally proposed by Charles Darwin </li></ul></ul>
  6. 6. <ul><li>Over millions of years natural selection resulted in the variety of life we see today </li></ul><ul><li>Most scientists believe that changes came about in spurts due to environmental changes </li></ul><ul><li>Existing organisms adapt and become new species as they fill niches left by extinct species </li></ul>
  7. 7. Scientists theorize… <ul><li>Single celled organisms evolved from independent existence to life in colonies </li></ul><ul><ul><li>Which then evolved into multicellular organisms </li></ul></ul><ul><ul><li>Lived </li></ul></ul>
  8. 8. Ocean Zones <ul><li>Water portion </li></ul><ul><li>pelagic </li></ul><ul><ul><li>Neritic: between low tide & edge of continental shelf </li></ul></ul><ul><li>Oceanic </li></ul><ul><ul><li>Epipelagic: sunlight penetrates, life </li></ul></ul><ul><ul><li>Mesopelagic: some light, not much life </li></ul></ul><ul><ul><li>Bathypelagic: deep </li></ul></ul><ul><ul><li>Abyssalpelagic: deeper </li></ul></ul><ul><ul><li>Hadalpalagic: deepest (Hades= hell) </li></ul></ul>
  9. 9. <ul><li>The Sea floor </li></ul><ul><li>Benthic zone </li></ul><ul><ul><li>Littoral: intertidal </li></ul></ul><ul><ul><li>Shelf: low tide – cont. shelf </li></ul></ul><ul><ul><li>Bathyal: deep </li></ul></ul><ul><ul><li>Abyssal: deeper </li></ul></ul><ul><ul><li>Hadal: deepest </li></ul></ul>
  10. 10. Marine Lifestyles <ul><li>Marine scientists classify life into 3 lifestyles: </li></ul><ul><ul><li>Plankton, nekton, benthos </li></ul></ul><ul><li>Plankton: drift with ocean currents, can be zooplankton, phytoplankton </li></ul><ul><ul><li>Neuston are the plankton that float at the surface. Ex.? </li></ul></ul>
  11. 11. <ul><li>Nekton: swimmers </li></ul><ul><ul><li>Examples? </li></ul></ul><ul><ul><li>Most are vertebrates </li></ul></ul><ul><ul><li>Most of the predators are nekton </li></ul></ul>
  12. 12. <ul><li>Benthos: live on or in the bottom, can move about or be sessile. </li></ul><ul><ul><li>Epifauna: animals that live on the sea floor </li></ul></ul><ul><ul><li>Epiflora: plants that live on the sea floor </li></ul></ul><ul><ul><li>Infauna: live partially or fully buried in sea floor </li></ul></ul>
  1. A particular slide catching your eye?

    Clipping is a handy way to collect important slides you want to go back to later.

×