An oak tree may produce thousands of acorns, which squirrels bury or eat. Why does the tree make so many acorns? Why might a plant whose seeds disperse far from the...

An oak tree may produce thousands of acorns, which squirrels bury or eat. Why does the tree make so many acorns? Why might a plant whose seeds disperse far from the parent have better reproductive success than one whose seeds fall at the base of the parent plant?

Places with short growing seasons tend to have less sunlight, so they spend more of their time in winter and darkness. By being evergreen. Conifers can continue to undergo photosynthesis, even during these times that would have to lose their leaves in order to survive the cold temperatures. They can actually keep their needles up, and they can continually produce energy from the slim amount of sunlight that's available to them. This helps them to thrive in these environments, where other plants might not get enough energy during the short growing seasons.

When pines and other Conifers lived in areas which have short growing seasons, they have much less access to sunlight, so they're often spending their time in the darkness of winter. When that sun comes around, they better be ready to start doing photosynthesis and taking advantage of the growing season to develop. So if they didn't have evergreen nature than they would have to start all over from leaf buds in order to get ready to actually photosynthesize. So by not letting go of their photosynthetic structures like other plans to do losing their leaves during the winter there ready to go when the sun comes around and they can immediately start growing using the needles that they have kept throughout the winter. And this is a huge advantage in areas restructurings.

It's about the type of reproduction that would be best in the situation where you have a changing environment. So the idea is that we have a plant and it lives in a site with changing soil conditions. And obviously soil is very important to plants, So this could be very important in the successful reproduction of this plant. And the question is, if this plant could twos, uh, would it be better for the plant to reproduce a sexually? Or would it be better for the plant to produce sexually and remember that the difference would be the genetic diversity of the offspring? If you had a sexual reproduction, then all the baby plants would basically be clones of the parental plant, and so there would be no genetic variation or no genetic diversity in the offspring. They would all be exactly like parental plant. And the problem there is that if the soil conditions air changing, if this parental plants genes are particularly good sweet for coping with the changing soil, then that will also be true of all these a sexually reproduced offspring. They will be have the same mill eels, and so they will face the same challenges. If you have sexual reproduction, however, than the offspring will be much more genetically diverse. And the advantage in a conditions like this of having genetically diverse offspring is that it may be that one or perhaps a handful of these genetically diverse offspring are better adapted to the change in so conditions than the parental plan. So there's a greater opportunity, a greater chance that one of the offspring will be better adapted to the changing soil and will be more likely to survive. So a greater chance of adaptation a good rule of thumb is, yeah, sexual reproduction is favored in changing conditions on that's often the reason I'll just believe that sexual reproduction occurs is because conditions are changing in one way or another, and it's good to have genetically diverse offspring to cope with those changes.

This question asked us to explain why diatoms must reproduce sexually occasionally. So Dai Adams are able to reproduce both sexually and a sexually. And this is actually quite interesting because the A sexual reproduction refers to a my tonic process where we undergo my toe sis and the, uh, daughter cells the offspring. They're going to be genetically identical to the parents out, whereas sexual reproduction involves my oh sis and my hostess allows for a little bit more genetic variation. But it also involves a change employees. So we're going to be taking a parent's out that is going to be deployed, and we are going to produce from this half Floyd often. So we're changing our employees from being too n to becoming single men on. We'll go over why this occurs in just a moment here. But just to get an understanding of this, the diadem can start off as just a single dad. Um, what's the years? They're going to be our parent, and it will undergo my toe sis, so it will reproduce a sexually continuously. But the thing is is that it produces two smaller diatoms, and then eventually we keep going until a minimum sighs is reached. And once we reach that cut off point, we swing into my oh sis. And then we have these game meats that are going to unite to produce a zygote. And then that saga will develop in tweet. Ah, full size diadem. So, as you can see, we are going to maintain the size of the diadem over multiple generations. So although the size will decrease, the overall net change in size will be zero after this whole cycle is complete. So why do diatoms reproduce sexually only occasionally? Well, it is because they will reach the minimum size for their subs on once they reach that minimum size, they have to go through sexual biotic division. And then these gametes will unite to form a zygote. And that's I goat. Just to point out the game. Is there going to be Hap Lloyd? Whereas ours ago, it is going to be deployed. Ah, and then our fully formed cell also be deployed. And just to be consistent here, well, right out of employees numbers. As you can see here, the catch is when you reach that minimum size, that is when you have to undergo this sexual reproduction or my oh sis,