Categorii: Tot - relationships - habitat - appearance - behaviour

realizată de Zarina Mitchell 8 ani în urmă

2001

Grizzly Bears

Grizzly bears, scientifically known as Ursus Arctos Horribilis, have a lifespan of up to 26 years and inhabit diverse regions across North America and Northern Eurasia. These omnivorous mammals are known for their intelligence, strong memory, and the need to consume large quantities of food in preparation for hibernation.

Grizzly Bears

Present

Selective pressures could lead to evolution.

The ice age. Grizzly bears became omnivores - because their original food (meat) was dying off - and started to hibernate in this time period.

Biotic

Abiotic

The bear and climate. The climate could change and the bear is forced to change with it.

Due to little food resources bears are forced to do things that bears wouldn't normally do. In Alaska, some bears break into people's homes looking for food. Some bears in Russia do eat humans because their natural food source is dying off.

Grizzly Bears can live up to 22-26 years

Sub-alpine meadows, dense forests, open plains, and Arctic tundra

Bibliography: https://en.wikipedia.org/wiki/Grizzly_bear http://www.defenders.org/grizzly-bear/basic-facts http://www.animalfactguide.com/animal-facts/grizzly-bear/ https://prezi.com/iac58jrfzhan/the-evolution-of-the-grizzly-bear/ https://sites.google.com/site/grizzlybearcaston/blog/symbioticrelationships http://scribol.com/environment/animals-environment/alaskan-grizzly-bears-fishing-for-salmon/ http://www.answers.com/Q/What_is_a_example_of_commensalism_in_a_grizzly_bear?#slide=1

North American Brown Bear/Grizzly Bear (Ursus Arctos Horribilis)

Reproduction

Litter size: 1-4 cubs
Sexually mature when 4 or 5 years old

Appearance

Large nostrils to help with smelling out prey
Grizzly Bears have a better sense of smell than blood hounds.
(Standing) 8 feet tall
Fur can be a light cream colour to black.
Claws (2-4 inches long)*
*Due to these triats grizzly bears have amazing digging abilities
Hump on shoulder*
Concave faces

Diet

Omnivores
Seeds, berries, roots, grass, fungi
Deer, elk, fish, dead animals, insects

Due to environment change, some grizzly bears eat cattle and sheep

Evolution

Fossil
Past vs Future In the past grizzly bears had a thicker skull. In the present grizzly bears have a more flat skull.
Past grizzly bear skeleton
DNA
Looking at the family tree. By doing this we can see the differences and similarities.
Biographical
Family Tree: Ursavus Elemenis | Protursus | Auvegne Bear | Etruscan Bear | Grizzly Bear
(An idea) My Cladogram https://www.lucidchart.com/documents/view/e2c80431-2b41-4aa2-93c0-9890c2af387d

Relationships

Commensalism
Bears and humans. Humans could go camping near a bears habitat. Usually bears would eat the trash that humans leave out.
Parasitism
Bears and lice. In this relationship the lice benefit because they have a giant food source, the bears are irritated and itchy. This relationship benefits the lice only.
Predator/prey
Bears and salmon. It is no surprise that grizzly bears benefit from this relationship. The salmon not so much. Grizzly bears get around to eating salmon before they reproduce. This is a bad thing right now due to the fact the other species - humans - are also eating a large portion of salmon.
Mutualism
Bears and plants. The bears eat the plants then later poop the seeds out. Then the seeds will start growing.

Behaviour

Highly intelligent
Great memory
Need to eat a lot in summer for hibernation
Females take care of cubs for 2-3 years
Not completely territorial. Bears are even seen sharing food* when there is little food to go around.
*For example, salmon streams

Natural Habitat

Northern Eurasia
Russia, Central Asia, China, Scandinavia, the Carpathian region (favouring Romania), and Caucasus
North America
Canada, United States (usually Alaska), and Mexico