The Wonder of the Fig
(Part 4- Dioecious Figs)
Now that the stage is set for grand evolutionary spectacle, we can
start tackling more challenging and interesting conflicts than the
previous one, and they begin when we move from ‘monoecious’ fig trees to
‘dioecious’ fig trees. A few but crucial things are different in the
dioecious trees.
In the earlier
example we talked about figs that contain within them both male and
female flowers. But dioecious fig trees will have all its male flowers
on one tree and all female flowers on other tree. So there will be a
male tree and a female tree, and male trees will make figs that contain
only male flowers with pollen, and female trees will make figs that
contain only female flowers that will go on form seeds.
Another crucial difference in the dioecious trees is that if a wasp lays
her eggs inside a female flower of a female tree, the eggs can never
grow in them due to various reasons, example the style of the female
flowers is just too long for the wasp to deposit her eggs. (in total
contrast to our earlier story of monoecious figs where the wasp eggs
feed on the growing seed of the pollinated female flowers).
And here's the most important part, the figs of the male trees also
contain “pseudo-female flowers” that don’t actually do anything for the
fig tree (directly!). All that those pseudo-female flowers do is provide
food for the baby wasps, mimic the structure and scent of the
real-female flowers, and nothing else.
To sum it up, here's what happens:
Female wasps emerge from the male figs and search for figs to pollinate
and lay their eggs in. If a female wasp gets inside the male fig with
"pseudo-female" flowers, her children will grow there and continue the
same cycle. But if the wasp enters a female fig with real-female
flowers, she will succeed in pollination, but fail in laying her eggs.
As you may have guessed, the female wasp is only directly "interested"
(in the special Darwinian sense, not a conscious one) in selecting male
flowers that have "pseudo-female" flowers, but the figs "interest" lies
in making the wasp enter both the male and female figs for a successful
pollination.
The balance is achieved because the male fig trees
and female fig trees will be naturally selected to look almost similar
to each other, thereby confusing the wasp and making her chances of
entering male and female figs almost equal. The male and female figs
look very much alike, and as I said before, the male fig also gives out
scent similar to female figs to confuse the wasp, along with being
structurally very similar!
This is just one conflict and its resulting balance, and there's more that we shall see in the next part.
Sources:
1) ‘Climbing Mount Improbable’, Richard Dawkins, 1996
2) http://nirmukta.com/2012/08/
3) www.figweb.org
4) http://www.jstor.org/stable/
Image credit: Simon van Noort (Iziko Museums) and Jean-Yves Rasplus (INRA) from www.figweb.org.
The Wonder of the Fig
(Part 4- Dioecious Figs)
Now that the stage is set for grand evolutionary spectacle, we can start tackling more challenging and interesting conflicts than the previous one, and they begin when we move from ‘monoecious’ fig trees to ‘dioecious’ fig trees. A few but crucial things are different in the dioecious trees.
(Part 4- Dioecious Figs)
Now that the stage is set for grand evolutionary spectacle, we can start tackling more challenging and interesting conflicts than the previous one, and they begin when we move from ‘monoecious’ fig trees to ‘dioecious’ fig trees. A few but crucial things are different in the dioecious trees.
In the earlier
example we talked about figs that contain within them both male and
female flowers. But dioecious fig trees will have all its male flowers
on one tree and all female flowers on other tree. So there will be a
male tree and a female tree, and male trees will make figs that contain
only male flowers with pollen, and female trees will make figs that
contain only female flowers that will go on form seeds.
Another crucial difference in the dioecious trees is that if a wasp lays her eggs inside a female flower of a female tree, the eggs can never grow in them due to various reasons, example the style of the female flowers is just too long for the wasp to deposit her eggs. (in total contrast to our earlier story of monoecious figs where the wasp eggs feed on the growing seed of the pollinated female flowers).
And here's the most important part, the figs of the male trees also contain “pseudo-female flowers” that don’t actually do anything for the fig tree (directly!). All that those pseudo-female flowers do is provide food for the baby wasps, mimic the structure and scent of the real-female flowers, and nothing else.
To sum it up, here's what happens:
Female wasps emerge from the male figs and search for figs to pollinate and lay their eggs in. If a female wasp gets inside the male fig with "pseudo-female" flowers, her children will grow there and continue the same cycle. But if the wasp enters a female fig with real-female flowers, she will succeed in pollination, but fail in laying her eggs.
As you may have guessed, the female wasp is only directly "interested" (in the special Darwinian sense, not a conscious one) in selecting male flowers that have "pseudo-female" flowers, but the figs "interest" lies in making the wasp enter both the male and female figs for a successful pollination.
The balance is achieved because the male fig trees and female fig trees will be naturally selected to look almost similar to each other, thereby confusing the wasp and making her chances of entering male and female figs almost equal. The male and female figs look very much alike, and as I said before, the male fig also gives out scent similar to female figs to confuse the wasp, along with being structurally very similar!
This is just one conflict and its resulting balance, and there's more that we shall see in the next part.
Sources:
1) ‘Climbing Mount Improbable’, Richard Dawkins, 1996
2) http://nirmukta.com/2012/08/
3) www.figweb.org
4) http://www.jstor.org/stable/
Image credit: Simon van Noort (Iziko Museums) and Jean-Yves Rasplus (INRA) from www.figweb.org.
Another crucial difference in the dioecious trees is that if a wasp lays her eggs inside a female flower of a female tree, the eggs can never grow in them due to various reasons, example the style of the female flowers is just too long for the wasp to deposit her eggs. (in total contrast to our earlier story of monoecious figs where the wasp eggs feed on the growing seed of the pollinated female flowers).
And here's the most important part, the figs of the male trees also contain “pseudo-female flowers” that don’t actually do anything for the fig tree (directly!). All that those pseudo-female flowers do is provide food for the baby wasps, mimic the structure and scent of the real-female flowers, and nothing else.
To sum it up, here's what happens:
Female wasps emerge from the male figs and search for figs to pollinate and lay their eggs in. If a female wasp gets inside the male fig with "pseudo-female" flowers, her children will grow there and continue the same cycle. But if the wasp enters a female fig with real-female flowers, she will succeed in pollination, but fail in laying her eggs.
As you may have guessed, the female wasp is only directly "interested" (in the special Darwinian sense, not a conscious one) in selecting male flowers that have "pseudo-female" flowers, but the figs "interest" lies in making the wasp enter both the male and female figs for a successful pollination.
The balance is achieved because the male fig trees and female fig trees will be naturally selected to look almost similar to each other, thereby confusing the wasp and making her chances of entering male and female figs almost equal. The male and female figs look very much alike, and as I said before, the male fig also gives out scent similar to female figs to confuse the wasp, along with being structurally very similar!
This is just one conflict and its resulting balance, and there's more that we shall see in the next part.
Sources:
1) ‘Climbing Mount Improbable’, Richard Dawkins, 1996
2) http://nirmukta.com/2012/08/
3) www.figweb.org
4) http://www.jstor.org/stable/
Image credit: Simon van Noort (Iziko Museums) and Jean-Yves Rasplus (INRA) from www.figweb.org.
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