Uploaded August 2023 | Updated September 2026, 1 day ago
You can find all my A Level Biology videos fully indexed at freesciencelessons.co.uk/a-level-revision-videos/a-level-biology
In this video, we look at evolution by natural selection. First we explore the idea of selection pressures and the effect of these on organisms. We then look at the process of natural selection. Finally, we look at how natural selection has lead to the development of antibiotic-resistant bacteria and pesticide-resistant insects.
Image credits:
Polyphemus Moth
commons.wikimedia.org/wiki/File:Antheraea_polyphemus_-_Polyphemus_Moth.jpg
Ilona Loser, CC BY-SA 4.0 creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Dolphin
commons.wikimedia.org/wiki/File:Dolphind.jpg
sheilapic76, CC BY 2.0 creativecommons.org/licenses/by/2.0, via Wikimedia Commons
Marram Grass
commons.wikimedia.org/wiki/File:Marram_Grass,_Goswick_Sand_Dunes_-_geograph.org.uk_-_2135294.jpg
Marram Grass, Goswick Sand Dunes by Mick Garratt, CC BY-SA 2.0 creativecommons.org/licenses/by-sa/2.0, via Wikimedia Commons
Myoxocephalus scorpius PAQ
commons.wikimedia.org/wiki/File:Myoxocephalus_scorpius_PAQ.jpg
upload.wikimedia.org/wikipedia/commons/b/b8/Myoxocephalus_scorpius_PAQ.jpg
Placental mole
en.wikipedia.org/wiki/File:ScalopusAquaticus.jpg#file
Kenneth Catania, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Moorland stream
commons.wikimedia.org/wiki/File:Moorland_Stream_-_geograph.org.uk_-_2350455.jpg
Moorland Stream by Philip Platt, CC BY-SA 2.0 creativecommons.org/licenses/by-sa/2.0, via Wikimedia Commons
Wolf
commons.wikimedia.org/wiki/File:Front_view_of_a_resting_Canis_lupus_ssp.jpg
Gary Kramer, Public domain, via Wikimedia Commons
Rabbit with myxomatosis
commons.wikimedia.org/wiki/File:Rabbit_with_Myxomatosis_1(RLH).jpghttps://commons.wikimedia.org/wiki/File:Rabbit_with_Myxomatosis_1(RLH).jpg
Richard Harvey, CC BY 3.0 creativecommons.org/licenses/by/3.0, via Wikimedia Commons
Snowy moor
commons.wikimedia.org/wiki/File:A_snowy_Rannoch_Moor_-_geograph.org.uk_-_1638676.jpg
Dave Fergusson / A snowy Rannoch Moor
Desert
commons.wikimedia.org/wiki/File:Desert_(9).jpg
Mostafameraji, CC BY-SA 4.0 creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Charles Darwin
commons.wikimedia.org/wiki/File:Charles_Darwin_aged_51.jpg
Messrs. Maull and Fox, Public domain, via Wikimedia Commons
Snowshoe 1
commons.wikimedia.org/wiki/File:MK04608_Snowshoe_Hare_(Banff).jpg
Martin Kraft, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Snowshoe 2
commons.wikimedia.org/wiki/File:Snowshoe_hare_(52924634241).jpg
USFWS Midwest Region from Midwest Region, United States, Public domain, via Wikimedia Commons
Snowshoe 3
commons.wikimedia.org/wiki/File:Lepus_americanus_5459.JPG
Walter Siegmund, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Snowshoe 4
commons.wikimedia.org/wiki/File:Snowshoe_Hare_(Lepus_americanus)_-_Gros_Morne_National_Park,_Newfoundland_2019-08-20.jpg
Ryan Hodnett, CC BY-SA 4.0 creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Snowshoe 5
commons.wikimedia.org/wiki/File:A_snowshoe_hare_(b35f0212-39a8-4d9b-bb2f-0cbfbac39213).jpg
English: Mary Lewandowski, Public domain, via Wikimedia Commons
Snowshoe 6
commons.wikimedia.org/wiki/File:SNOWSHOE_HARE_(Lepus_americanus)_(8-20-13)_stunner_c_g,_n-w_conejos_co,_co_(3)_(9592430167).jpg
ALAN SCHMIERER, CC0, via Wikimedia Commons
Canada Lynx
en.wikipedia.org/wiki/File:Canada_lynx_by_Michael_Zahra_(cropped).jpg
Michael Zahra, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Bobcat
commons.wikimedia.org/wiki/File:Bobcat_at_Columbus_Zoo_Boo.jpg
Becker1999 (Paul and Cathy), CC BY 2.0 creativecommons.org/licenses/by/2.0, via Wikimedia Commons
Marten
commons.wikimedia.org/wiki/File:Newfoundland_Pine_Marten.jpg
Bailey Parsons, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Colorado potato beetle
en.wikipedia.org/wiki/File:Colorado_potato_beetle.jpg
Scott Bauer USDA ARS
Staph A
commons.wikimedia.org/wiki/File:Staphylococcus_aureus_VISA_2.jpg
Content Providers(s): CDC/ Matthew J. Arduino, DRPH Photo Credit: Janice Haney Carr, Public domain, via Wikimedia Commons
You can find all my A Level Biology videos fully indexed at freesciencelessons.co.uk/a-level-revision-videos/a-level-biology
In this video, we look at evolution by natural selection. First we explore the idea of selection pressures and the effect of these on organisms. We then look at the process of natural selection. Finally, we look at how natural selection has lead to the development of antibiotic-resistant bacteria and pesticide-resistant insects.
Image credits:
Polyphemus Moth
commons.wikimedia.org/wiki/File:Antheraea_polyphemus_-_Polyphemus_Moth.jpg
Ilona Loser, CC BY-SA 4.0 creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Dolphin
commons.wikimedia.org/wiki/File:Dolphind.jpg
sheilapic76, CC BY 2.0 creativecommons.org/licenses/by/2.0, via Wikimedia Commons
Marram Grass
commons.wikimedia.org/wiki/File:Marram_Grass,_Goswick_Sand_Dunes_-_geograph.org.uk_-_2135294.jpg
Marram Grass, Goswick Sand Dunes by Mick Garratt, CC BY-SA 2.0 creativecommons.org/licenses/by-sa/2.0, via Wikimedia Commons
Myoxocephalus scorpius PAQ
commons.wikimedia.org/wiki/File:Myoxocephalus_scorpius_PAQ.jpg
upload.wikimedia.org/wikipedia/commons/b/b8/Myoxocephalus_scorpius_PAQ.jpg
Placental mole
en.wikipedia.org/wiki/File:ScalopusAquaticus.jpg#file
Kenneth Catania, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Moorland stream
commons.wikimedia.org/wiki/File:Moorland_Stream_-_geograph.org.uk_-_2350455.jpg
Moorland Stream by Philip Platt, CC BY-SA 2.0 creativecommons.org/licenses/by-sa/2.0, via Wikimedia Commons
Wolf
commons.wikimedia.org/wiki/File:Front_view_of_a_resting_Canis_lupus_ssp.jpg
Gary Kramer, Public domain, via Wikimedia Commons
Rabbit with myxomatosis
commons.wikimedia.org/wiki/File:Rabbit_with_Myxomatosis_1(RLH).jpghttps://commons.wikimedia.org/wiki/File:Rabbit_with_Myxomatosis_1(RLH).jpg
Richard Harvey, CC BY 3.0 creativecommons.org/licenses/by/3.0, via Wikimedia Commons
Snowy moor
commons.wikimedia.org/wiki/File:A_snowy_Rannoch_Moor_-_geograph.org.uk_-_1638676.jpg
Dave Fergusson / A snowy Rannoch Moor
Desert
commons.wikimedia.org/wiki/File:Desert_(9).jpg
Mostafameraji, CC BY-SA 4.0 creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Charles Darwin
commons.wikimedia.org/wiki/File:Charles_Darwin_aged_51.jpg
Messrs. Maull and Fox, Public domain, via Wikimedia Commons
Snowshoe 1
commons.wikimedia.org/wiki/File:MK04608_Snowshoe_Hare_(Banff).jpg
Martin Kraft, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Snowshoe 2
commons.wikimedia.org/wiki/File:Snowshoe_hare_(52924634241).jpg
USFWS Midwest Region from Midwest Region, United States, Public domain, via Wikimedia Commons
Snowshoe 3
commons.wikimedia.org/wiki/File:Lepus_americanus_5459.JPG
Walter Siegmund, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Snowshoe 4
commons.wikimedia.org/wiki/File:Snowshoe_Hare_(Lepus_americanus)_-_Gros_Morne_National_Park,_Newfoundland_2019-08-20.jpg
Ryan Hodnett, CC BY-SA 4.0 creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Snowshoe 5
commons.wikimedia.org/wiki/File:A_snowshoe_hare_(b35f0212-39a8-4d9b-bb2f-0cbfbac39213).jpg
English: Mary Lewandowski, Public domain, via Wikimedia Commons
Snowshoe 6
commons.wikimedia.org/wiki/File:SNOWSHOE_HARE_(Lepus_americanus)_(8-20-13)_stunner_c_g,_n-w_conejos_co,_co_(3)_(9592430167).jpg
ALAN SCHMIERER, CC0, via Wikimedia Commons
Canada Lynx
en.wikipedia.org/wiki/File:Canada_lynx_by_Michael_Zahra_(cropped).jpg
Michael Zahra, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Bobcat
commons.wikimedia.org/wiki/File:Bobcat_at_Columbus_Zoo_Boo.jpg
Becker1999 (Paul and Cathy), CC BY 2.0 creativecommons.org/licenses/by/2.0, via Wikimedia Commons
Marten
commons.wikimedia.org/wiki/File:Newfoundland_Pine_Marten.jpg
Bailey Parsons, CC BY-SA 3.0 creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Colorado potato beetle
en.wikipedia.org/wiki/File:Colorado_potato_beetle.jpg
Scott Bauer USDA ARS
Staph A
commons.wikimedia.org/wiki/File:Staphylococcus_aureus_VISA_2.jpg
Content Providers(s): CDC/ Matthew J. Arduino, DRPH Photo Credit: Janice Haney Carr, Public domain, via Wikimedia Commons
