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On the Architectural Features of Ecological and Biological Networks Universidad de Granada Facultad de Ciencias On the Architectural Features of Ecological and Biological Networks Tesis presentada por Virginia Dom´ınguez Garc´ıa para obtener el grado de Doctora por el Programa de Doctorado en F´ısica y Matematicas´ Director: Miguel Angel´ Munoz~ Mart´ınez Diciembre 2014 Departamento de Electromagnetismo y F´ısicade la Materia e Instituto Carlos I de F´ısicaTe´oricay Computacional Agradecimientos En primer lugar me gustar´ıadecir que este trabajo no habr´ıasido posible sin la ayuda de mucha, MUCHA, gente. Voy a comenzar agradeciendo a mi director, MA Mu~noz,por su continuo optimismo y entrega, sin los que indudablemente me habr´ıasido infinitamente m´asduro llevar a cabo este trabajo, as´ıcomo por su paciencia y dotes de redacci´on (que tan dif´ıcilesson de igualar). Tambi´enquiero agradecer a mis otros colaboradores, Sam, Simone y Luca. Bueno, a Sam quiero agradecerle, en el plano laboral, la fe ciega en nuestro trabajo y que nos haya demostrado que la perseverancia y la insistencia dan sus frutos. Tambi´enme gustar´ıaagradecerle los muchos cambios de opini´ona la hora de hacer las gr´aficasy dem´as,lo que sin duda me ha llevado a dominar el fino arte de los scripts de bash (seguramente no habr´ıaaprendido tan deprisa sin su ayuda, jeje). Espero que sigamos colaborando en alguna de los cientos de ideas que tienes. A Simone quiero decirle que ha sido un aut´entico placer trabajar con ´el,y que espero que volvamos a hacerlo. En cualquier caso siempre quedar´anlos FisEs para que Jordi te saque a bailar el \annealing" o el \ferromon". Quiero tambi´enagradecer a todo el grupo de F´ısicaEstad´ıstica de la UGR por crear un ambiente de trabajo al que realmente da gusto ir: Paco, Pablo, Lacomba, Joaquin Jr., Pedro (gracias por ense~narmeF´ısicaEstad´ısticade nuevo, y todo lo que se puede hacer con ella...., as´ıcomo por el amplio repertorio de bromas que amenizan la jornada en el gineceo) y, por supuesto, J. Marro (a quien a partir de ahora asociar´eirremediablemente con los extintores). Hay que decir que estar una ma~nanajuntos pegando sobres es una buena actividad de grupo. Espero veros en los pr´oximosGranada Seminar, que cada d´ıatienen m´ascach´e. A Jose le quiero dedicar un p´arrafoespecial porque, como todos sabemos, sin ´el la productividad del grupo caer´ıaen picado (y la impresora no volver´ıaa funcionar): v vi gracias Jose, por tu paciencia y por reservarme a kratos21 cada vez que me hac´ıafalta, por ayudarme con la programaci´on,con la web, y en general porque si, que eres super apa~nao. A los otros becarios y/o post docs (actuales y pasados), qu´edecir .... en general que muchas gracias por ser como sois. A Nico gracias por currarse esas pedazo de partidas de Arkham Horror, con palomitas, palomitero y de t´o.A Paula porque ha sido genial compartir tant´ısimasexperiencias con ella, y porque ya somos compa~nerasde cuarto habituales. A Jordi porque es que es una \gorda postrera" :p , y porque menos a la hora de salir (que a veces es un \rollo") siempre lo da todo. Gracias por ense~narme C+ (jeje, espero que al menos hayas descubierto cosas nuevas con la de cosas raras que te he preguntado), la plantilla de la tesis y los chistes hasta la hora de dormir. Mil gracias. A Sam tambi´enle voy a agradecer en esta secci´on,pero en este caso por ense~narme casi todos los bares que me s´ede Granada, y junto a Sebas, Carlos y Jes´us,gracias por las horas de conversaciones interesantes, y alguna que otra fiesta. Sin duda han hecho de mi estancia en Granada algo mucho m´asentretenido. A Paolo gracias por ense~narmea usar Python en un d´ıa! (aun no me lo creo, eres un crack). Espero que te vaya muy bien por Alemania. A Vanessa gracias por los English Fridays. Al nuevo protobecario, Pablo, mucha suerte. A los \visitantes" tambi´enquiero agradecerles: a Lui~no,por ser un personaje, que eres genial. Estoy segura de que alg´und´ıate har´as famoso (aunque a´unno estoy muy segura de en qu´e,jeje). A los visitantes de m´as lejos: Alejandro, Nara, Leticia y Facundo, tambi´engracias por muchas conversaciones interesantes, y a Leti especialmente por animarme a ir a la piscina. Gracias tambi´en por la c´alidaacogida en La Plata. Espero que os vaya todo estupendo. A los becarios (o no) de los otros departamentos, que yo generalmente englobo como \los amigos de Jordi": Leo, German, Migue, Ma del Mar, Rafa, Alice, Miki, Alvaro,´ Javi, Fernando, Ben ..(y muchos m´as)..gracias por ser tan divertidos y entregados, <y por tener unas ideas tan guays para los regalos!. Sois estupendos. Me hac´eissentir un poco m´ascomo en casa. Ahora gracias a los otros becarios de la F´ısicaEstad´ısticade Espa~na(y Catalu~na, jeje) a la mayor´ıade los cuales conoc´ıen la epiqu´ısimae irrepetible escuela de verano del Gefenol en Benasque, y que hicieron de esa escuela una experiencia inolvidable. Especialmente a Edo, Sveto, Edgar, Dani y Uri, les quiero agradecer por provocar la vii barbacoa m´asespectacular en la que he estado y (posiblemente) estar´e. Las fotos no tienen precio, por cierto. <Ah! y a Paula por poner la casa ..... Villa Maravilla ...... Now, I'll turn to english to thank prof. Thilo Gross and Rudolf Lars for working with me in my brief stay in Bristol, and specially to prof. Gross for letting me know about the many routes in and around Bristol, and showing me Brandon Hill, one of my favourites places in Bristol. I'd like to thank all the students in the Buncar for being so nice, and specially Dan and Alex for keeping the resurrected plant alive!. Thanks to Oct & Corra for showing me the city, sharing swing lessons, and, in general, making my stay in Bristol something to remember with a smile. Bueno y ahora a las personas que, aunque no est´andirectamente relacionadas con este trabajo, quiero nombrar aqu´ıporque de una manera u otra todas han contribuido a que tenga una condici´onmental suficientemente buena para trabajar, (vamos, que les he dado la chapa alguna vez hasta quedarme tranquila). Primero quiero agradecer a mis padres por todo lo que me han dado. A mi madre, no creo que pueda resumirlo en una frase, pero gracias por seguir adelante sin siquiera pensarlo. Tu me has ense~nado c´omoaguantar lo que venga, y adem´ashacerlo casi siempre con una sonrisa. Y gracias por las croquetas de jam´on. A mi hermana, muchas gracias por ense~narmea ver el mundo c´omoes, y por demostrar que merece la pena luchar por nuestros derechos. A Juanjo, gracias por llevarme infinitas veces a la estaci´on,sin duda esta tesis no habr´ıa sido posible sin tu contribuci´on, jeje. A mis amigxs de la facultad: Ana Ansar, Menchuch´u,YoJavi, Anahoria, Elisa, Marina Normal, JP, Octavio, Marina Fashion, Amparo, Domingo, de la Torre, Curro, Migue: illo, sois magn´ıficxs,y ya est´a.Gracias por leeros mis infinitos mails sobre las noticias, comentarlos y en general poder discutir de toda esta mierda de una manera abierta y l´ogica.YoJavi, gracias por leerte mis retweets, XD. Much´ısimasgracias por las incontables horas de risas, chistes, confidencias y dem´as. Sin vosotros mi vida no ser´ıala misma, ser´ıamucho peor. A Salva, evidentemente gracias por todo lo anterior, adem´asde por saberse todas las rutas de la sierra de Espa~na,aparentemente, pero sobre todo gracias por ser c´omoeres, por estar ah´ısiempre, y por sacarme sonrisas cuando nadie m´aspuede. Ah, y por mantener la calma cuando yo peto, eso tambi´en,jejeje. A los habitantes de la mansi´onmapache, gracias por acogerme innumerables veces. Mucha suerte con la Jer´onima. A Morcar le quiero dar las gracias por dirigir las viii partidas de Hero Quest, y espero que vuelva a dirigir m´asdentro de poco, o tendremos que resucitar a Vittorio para que imparta justicia. A mis amigxs del colegio, Mar´ıa,Ana, Marta, Marta y Crama: gracias tambi´enpor ser c´omosois. Siempre est´aisconmigo, todxs. A Luis, sensei del Musubi, quiero agradecerle sus reflexiones y ense~nanzas,en par- ticular la de que a veces hay que mantener el sitio. Nunca olvidar´ela frase \si eres siempre agua, al final te saldr´achepa". Gracias a todos los integrantes del dojo, porque el buen ambiente que me llevo a mi casa me ha ayudado sin duda a realizar este trabajo con m´asalegr´ıa.Quiero agradecer especialmente a Espe, Carlos, Thinker, y Paula: me encanta compartir reflexiones, aikido, cervezas y conversaciones con vosotros. Y finalmente va siendo hora de agradecer a todos esos bi´ologosque no conozco (muchos de ellos becarios, sospecho) pero que han pasado horas y horas, y horas, reuniendo todos los datos de redes tr´oficas,mutualistas y dem´as.Sin vuestro trabajo, el nuestro no habr´ıasido posible. Gracias, adem´as,por ponerlo accesible (en la mayor´ıa de los casos). Tambi´enquiero agradecer sin duda a Wikimedia Commons, y a toda la gente que colabora subiendo fotos ah´ıy a otras plataformas sin copyright. Sin vuestras fotos la portada de esta tesis no habr´ıa sido posible. Y ya que estamos, gracias a Grooveshark (y al adblock) por sus incontables horas de m´usica,sin las que seguramente este trabajo se me habr´ıahecho much´ısimom´ascuesta arriba.
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