Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
remaining cards
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how


Bio Midterm 2

Env of early tetrapods -same time animals were "invading the land" -mainly gymnosperms (water dependent) -swamp habitats and very food rich
evolution of tetrapods -lungfish with fins were ancestors -pectoral and pelvic find homologous to fore- & hind- limbs -lungfish are sister group to tetrapods bc dna evidence
tiktaalik and acanthostega -found in cold regions -lived in tropical warm climates -fossils moved with tectonic plates
genius tiktaalik -around 375 m.y.a -"fishpod" -between fish & tetrapod (characteristics of both groups)
tiktaalik trais 1. primitive neck -allowed head movement 2. forelimb bones 3. had pelvic girdle but not good 4. had ribs
genius acanthostega -lived around 360 mya -mainly aquatic but first tetrapod -well developed pelvic and pectoral girdles
acanthostega habitat -benthic organism on bottom of pools -able to come on land and crawl
traits of acanthostega 1. well developed muscular laterally compressed tail 2. well-developed gills 3. relatively well developed legs (weight bearing) 4. had toes 5. weak ribs and small lungs
Exaptation -an organism possesses a trait that was used for one purpose, but happened to be useful for other purposes -suggests teleology but NO!
exaltation examples 1. evolution of tetrapods (legs evolved first before tetrapods moved to land) 2. feathers(originally used for insulation but now used for flight
homologous -similar position, structure, and evolutionary origin, but not same function
Created by: 1186541148036268