Post on 14-Jan-2016
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Today: Grizzly Bears
We are only one of millionsofspeciesonearth.
Ecological Interconnections
Grizzly Bears
Grizzly bears are big.
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 28
How are bears related to each other?
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 15
12,000 years ago: the grizzly ancestor short-faced bear
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 17 and 23
Short-faced vs grizzly bears
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 78
Grizzly bears live most of their lives alone
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 78
Grizzly bears live most of their lives alone.
What do they do?
… mostly eat
What do grizzly bears eat?
Ray deLucia and the Grizzly Bear Fight AMNH photo # 296899 Courtesy of the American Museum of Natural History Library Services
Different mouth and teeth structures can tell about an animal’s diet
Fig 41.18
Grizzly bear teeth
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 54
cat
dog
grizzly
panda
Different teeth and diets
Carnivores have a short digestive system
Herbivores have a long digestive system
Fig41.19
HumansBears
Both humans and grizzly bears are omnivores.Our digestive systems can tell us about our ancestors.
Fig 41.19
About 75% of their diet is plants
They also eat carrion.
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 85
Some grizzlies are excellent predators, but most eat carrion.
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 186
Grizzlies constant search for food can lead to conflicts with humans.
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 215
Grizzlies constant search for food can lead to conflicts with humans.
There is not much to eat in winter...
Bears from temperate climates sleep over the winter in a den.(not hibernation)
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 62 and 63
Grizzlies have an amazing ability to gain and lose weight.
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 59
Grizzly reproduction
winter
fall
summer
spring
youngborn
den w/motherjuveniles
on own
Female Grizzly Bear reproductive cycle
Females are not fertile when caring for offspring
fertiliz-ation
Spring Summer Fall Winter(in den)
Birthyear
copulation delayed implantation gestation birth
Juvenileyear 1
Offspring with mom(lactation)
Offspring with mom(lactation)
Offspring with mom(lactation)
Offspring den with mom(lactation)
Juvenileyear 2
Offspring with mom(lactation)
Offspring with mom(lactation)
Offspring with mom(lactation)
Offspring den with mom(lactation)
Adolescentyear
Offspring with mom(lactation)
Offspring on own
Grizzly Bear Reproduction
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 58
Grizzly cubs are born in the den and are very small (~1 lb)
winter
fall
summer
spring
youngborn
den w/motherjuveniles
on own
Female Grizzly Bear reproductive cycle
Females are not fertile when caring for offspring
fertiliz-ation
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 76
Female bears are very protective of their young
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 77
Infanticide: males will try to kill young so that mother will become fertile
Historical Grizzly Bear range
Current Grizzly
Bear range
Habitat destruction and hunting have severely decreased grizzly populations in the U.S.
63 mi
54 mi
•466 mi of roads •950 mi of backcountry trails•97 trailheads•287 backcountry campsites
Yellowstone NP
Yellowstone Grizzly Bear population increases
Yellowstone NP is not big enough to support a viable grizzly bear population
Where do grizzly bears fit?
Are they important?
How much of our resources should we share with grizzly bears?
Bears (1993) Ian Stirling et al., Weldon Owen Pty Ltd pg 231
Animal behavior is unpredictable and inexplicable
Experiment Written Report:Title- Concisely describe your experiment.AuthorAbstract- Summarize your work. Do not exceed 250 words.Introduction-Results-Discussion-Materials and Methods-References- include: author name(s), article title, journal or book title, volume and page number, and year of publication
Staple your approved proposal to the back of your written report.
What is a reliable source?
xkcd.com
Building Blocks of Scientific Literature
peer review
What is peer review?
In a peer reviewed journal each article is looked at by an editor, and then it is then sent to two anonymous reviewers.
These reviewers send comments back to the editor.
After each article is sent to the editor, it is then sent to two anonymous reviewers.
These reviewers send comments back to the editor.
They give suggestions for improvement as well as an opinion about whether it should be published or not.
The editor then has three choices:
Accept paper as is. (rare)
Accept paper and ask for some changes.
Reject paper. (20-80% rejection rate in physical sciences*)
*Scholarly Consensus and Journal Rejection Rates. Lowell L. Hargens (Feb., 1988) American Sociological Review 53: 139-151andBang for Your Buck: Rejection Rates and Impact Factors in Ecological Journals. The Open Ecology Journal (2008) L.W. Aarssen, T. Tregenza, A.E. Budden, C.J. Lortie, J. Koricheva and R. Leimu 1: 14-19
Who reviews papers?
Other researchers knowledgeable in the field.
What is a reliable source?
xkcd.com
What is a reliable source?
What is a reliable source?
Can be a great source of sources...
What is a reliable source?
Who was the author(s)?Why was it written?Where was it published?Who checked/reviewed the article?
xkcd.com