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تسجيل مستخدم جديداختيار موازنة البذور: التعايش في نماذج بنوك البذور
Seed balancing selection: Coexistence in seedbank models
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نشر من قبل
Jos\\'e Luis P\\'erez J.L. P\\'erez
تاريخ النشر
2021
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English
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نحن نعتبر مجموعة سكانية مكونة من نوعين من الأفراد ؛ كل من يمكن أن ينتج ذرية في جزيرتين مختلفتين (كحالة معينة يمكن تفسير الجزر على أنها أفراد نشيطون أو نائمون). نقوم بنمذجة تطور السكان من كل نوع باستخدام انتشار من نوعين Feller مع الهجرة ، وندرس تكرار أحد الأنواع ، في كل جزيرة ، عندما يتم فرض الحجم الكلي للسكان في كل جزيرة ثابت في مجموعة مرات كثيفة. هذا يؤدي إلى حل SDE الذي نسميه nanymmetric ثنائي الجزيرتين عملية التردد. نحن نشتق خصائص هذه العملية ونحصل على حد كبير من السكان عندما يميل الحجم الإجمالي لكل جزيرة إلى اللانهاية. بالإضافة إلى ذلك ، نحسب تقلبات العملية حول حدها التعريفي. نحن نؤسس الظروف التي بموجبها تكون عملية التردد غير المتماثل ثنائية الجزيرتين. الثنائي عبارة عن سلسلة ماركوف ذات بعدين مستمر يمكن تفسيرها من حيث الطفرة ، التفرع ، التفرع المزدوج ، الاندماج ، ومصطلح جديد مختلط لترحيل التحديد. أيضًا ، نجري تحليل استقرار للنظام الديناميكي المحدد ونقدم بعض النتائج العددية لدراسة التثبيت وشكل جديد من تحديد الموازنة. عند التقييد على نموذج بنك البذور ، نلاحظ أن بعض مجموعات المعلمات تؤدي إلى تحديد التوازن. إلى جانب إيجاد طريقة أخرى تزيد بها الخزانات الجينية من التباين الجيني ، نجد أنه إذا تنافست مجموعة تضم بنكًا للبذور مع مجموعة لا تقوم بذلك ، فسيتمتع منتجو البذور بميزة انتقائية إذا كانوا يتكاثرون بشكل أسرع ، لكنهم لن يحصلوا عليها لها عيب انتقائي إذا كانت تتكاثر بشكل أبطأ: سيناريو الحالة الأسوأ هو موازنة التحديد.
We consider a population constituted by two types of individuals; each of them can produce offspring in two different islands (as a particular case the islands can be interpreted as active or dormant individuals). We model the evolution of the population of each type using a two-type Feller diffusion with immigration, and we study the frequency of one of the types, in each island, when the total population size in each island is forced to be constant at a dense set of times. This leads to the solution of a SDE which we call the asymmetric two-island frequency process. We derive properties of this process and obtain a large population limit when the total size of each island tends to infinity. Additionally, we compute the fluctuations of the process around its deterministic limit. We establish conditions under which the asymmetric two-island frequency process has a moment dual. The dual is a continuous-time two-dimensional Markov chain that can be interpreted in terms of mutation, branching, pairwise branching, coalescence, and a novel mixed selection-migration term. Also, we conduct a stability analysis of the limiting deterministic dynamical system and present some numerical results to study fixation and a new form of balancing selection. When restricting to the seedbank model, we observe that some combinations of the parameters lead to balancing selection. Besides finding yet another way in which genetic reservoirs increase the genetic variability, we find that if a population that sustains a seedbank competes with one that does not, the seed producers will have a selective advantage if they reproduce faster, but will not have a selective disadvantage if they reproduce slower: their worst case scenario is balancing selection.
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