Download presentation

Presentation is loading. Please wait.

Published byAlexandria Sommer Modified over 4 years ago

1
COMPETITION – COLONIZATION TRADE-OFF AND COEXISTENCE Ants and Acacia trees in Eastern Africa Angelica Cuevas Francesca Palmeira Irina Barros Mauricio Montellano Paulo Oliveira Raul Barriga

3
Acacia drepanolobium

5
Herbivory

6
Mutualism Acacia - Ants

7
Mutualism Acacia - Ants Shelter

8
Mutualism Acacia - Ants Shelter Food

9
Mutualism Acacia - Ants Shelter Food

10
THE SYSTEM Competition –Colonization trade-off

11
THE SYSTEM Competition –Colonization trade-off > Dispersion and Colonization >> Crematogaster sjostedtiC. mimosaeC. nigricepsTetraponera penzigi

12
THE SYSTEM Competition –Colonization trade-off > < Dispersion and Colonization Competition > < > < Crematogaster sjostedtiC. mimosaeC. nigricepsTetraponera penzigi

13
THE QUESTION How can the tree dynamics (growth, birth and death) affect the coexistence of the ants?

14
THE MODEL Competition –Colonization trade-off and Coexistence Strong Competitor Good Colonizer

15
THE MODEL Competition –Colonization trade-off and Coexistence Strong Competitor Good Colonizer Species 1

16
THE MODEL Competition –Colonization trade-off and Coexistence Strong Competitor Good Colonizer Species 2 Species 1

17
THE MODEL Competition –Colonization trade-off and Coexistence Young Mature

18
α > β μ m < μ y D < β α m > α y G e < G i THE MODEL Competition –Colonization trade-off and Coexistence Colonization rates Mortality rates Conquer and colonization rates Colonization rates for all ants Growth rates

19
dT ye /dt = rT m – G e T ye – α y T 1 T ye – β y T 2 T ye – μ y TT ye dT y1 /dt = α y T 1 T ye – G i T y1 – a y T 2 T y1 – μ y TT y1 dT y2 /dt = β y T 2 T ye + a y T 2 T y1 – G i T y2 – μ y TT y2 dT me /dt = G e T ye – α m T 1 T me – β m T 2 T me – μ m TT me dT m1 /dt = G i T y1 + α m T 1 T me – a m T 2 T m1 – μ m TT m1 dT m2 /dt = G i T y2 + β m T 2 T me + a m T 2 T m1 – μ m TT m2 THE MODEL Competition –Colonization trade-off and Coexistence Young empty trees Young – species1 Young – species 2 Mature empty trees Mature - species 1 Mature – species 2

20
RESULTS Competition and Coexistence There is coexistence! - Predominance of the strongest - Strongest win on the mature trees, and loose at the young one

21
RESULTS Evaluating change in Parameters - If the strongest species is fast enough, the Weakest disappears. - The growth of the trees is not essential to coexistence - Different death rates are important to the proportion of ants

22
RESULTS Evaluating change in Parameters - The Strongest must be, indeed, stronger then the Sp 1 in order to continue to exist.

23
THE MODEL 3 species Competition –Colonization trade-off and Coexistence Young Mature

24
RESULTS Competition and Coexistence There is also coexistence! - The middle species can survive alongside the others depending on the parameters.

25
RESULTS Evaluating change in Parameters At the start of the process, Sp1 increase. After the death of Sp2, Sp1 starts to decrease There is a “phase transition” on the number of coexisting ants species

26
RESULTS Evaluating change in Parameters

27
So this model predicts the existence of mature trees without ants. FIXED POINTS

28
CONCLUSIONS - Increase of Predominance of the strongest species depends of its rate of dispersion - Coexistence is possible because of the colonization-competition trade- off - The rate of growth and rate of birth affects the ratio between the species, but not necessarily the coexistence itself. - The coexistence depends of the rates of dispersion and colonization.

29
THANK YOU!

30
Questions?!

Similar presentations

OK

Data Analysis and Mathematical Models. The structure of a community is described in terms of species composition and diversity Communities are comprised.

Data Analysis and Mathematical Models. The structure of a community is described in terms of species composition and diversity Communities are comprised.

© 2019 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google